Finally finished it. Some observations with (probably) spoilers:
-Should probably start with the worst part to get it out of the way: the story elements are definitely the weakest link, both in the sense of being the least interesting aspect of the experience and in comparison to XBCX and XBC2. I know what some people will say: XBCX had a bad story. But note that I'm not just referring to the main narrative, but also other things like the setting and the characters. I'll treat those three things (main arc, setting, characters) separately briefly, but suffice to say, I think Aionios is less interesting than Alrest and Mira, and that brings the game down quite a bit for me, because the settings were a big part of what made X and 2 engaging for me story-wise.
The thing with Aionios is, there is a quite a bit of interesting worldbuilding potential here, especially with the two factions and the particular rules and quirks of the world. The problem is, we get to see very little of the way the world actually works in normal circumstances since we spend the whole game trying to bring it down. Take the Flame Clocks for example. So this was one aspect of living in Aionios that made it different, and at the beginning you even seem to get a mechanic for it and everything. But guess what? Pretty much at the beginning of the game the main cast frees itself from the Clock and from then on just smash the Flame Clocks wherever they go. Something that had the potential to be interesting quickly becomes nothing but a target to be destroyed. This is emblematic of the wider problem of having the world as something primarily to be torn down rather than something to be fleshed out. The worst part of the issue is the way the the factional peculiarities of the two nations - each based on different systems (one focused on mechanical tech, the other on ether) - ultimately don't really get a chance to shine because the whole point of interacting with the colonies and their commanders is to free them from said nations. The ending is the cherry on top when it comes to undermining Aionios within the grand scheme of the Xenoblade universe. Those who have seen it know what I'm talking about.
That is not to say that it's a bad setting overall, and it has some interesting concepts going for it. It seems to be going in a more dystopian direction than 2 and X, and I don't really have a problem with that. In fact, that's one of the things that prevents the disconnect between the cast and the world from ruining the whole thing on this level, as it means that there are many components of the story that synergize with that. Probably the most obvious one would be Moebius. While none of the Moebius characters has the charisma of say, Jin or Malos, the organization itself and the associated aesthetic does a good job of embodying the perturbing and inhuman nature of the status quo. In particular, I liked the notion that the individuals that were picked to be part of it were those that actually wished to perpetuate the state of the world and that much of what drove their actions as Consuls was a plain desire to have fun at the expense of those still trapped. Considering that this game is giving off major Matrix vibes, making the Consuls the opposite of cold machines and their agents was a nice touch. They are by far the most interesting faction.
There are other things that I liked about the world and I do think it's best part about the game's story. Overall, however, it's a step down from something like Alrest with its explorable Titans amid a sea of clouds or Mira and the sense of discovery and organic worldbuilding that it had.
As for characters. I have to say the main cast is brought down by some rather weak dialogue that makes it hard to find their motivations convincing (despite the fact that this is served in a silver platter due to the dystopian-esque setting). They were clearly going for something more grounded than XBC2, and I would have been cool with that, had the execution been better. As it stands, the characters feel a bit bland at times. They do have their distinctive traits, and I don't think they have to be as over-the-top as those of 2 to be good at all, but I just feel that they don't really have that much going for them, ultimately. The two exceptions may well be Noah and Mio, as they do rise above their tepid start eventually (especially thanks to the N and M arcs, but also some other side plots). I should also note that, in terms of characters, the highlight ends up being not the main cast but the recruitable heroes, which are both numerous and varied. Not to mention a lot of them have plenty of associated quests that flesh them out. I liked most of those, with Triton, Cammuravi, and Ethel probably being the highlights if I had to pick just a few. Even some of the more one-note characters were frankly fun to drag around, as they had some good designs (better than those of the main cast, for some reason).
The main plot itself starts on the boring side, but gets better as the game progresses, especially from the end of Chapter 4 onward. Despite that, it is consistently plagued by bad dialogue, overlong and poorly paced cutscenes, and a somewhat lackluster main villain, among other things. I'd still say it's mostly an okay story, by videogame standards, but clearly weaker than that of 2.
-Unlike the story, the gameplay of XBC3 is very well-rounded and has very few points that are outright weak. There is some wasted potential here and some things could have been better, but overall, if you are a gameplay-focused player and can enjoy a good game despite the story, there is plenty to sink one's teeth into.
I'll start with the character and party building, as that is the best part of the game. The game grants you a six-member party plus a seventh slot for heroes. That in itself is massive incline as far as I'm concerned, as when it comes to RPGs, my view is that the bigger the party the better. But that's not all, unlike in XBCX you can also change the classes of each of your main party members. Each party member (minus the hero) is, in fact, fully customizable. The fact that this game has a big, fully customizable party is by itself a big draw for me, as party building is a big part of what RPGs are about as far as I'm concerned.
There are around 25 classes to choose from, all falling within the three classic archetypes, but also offering a lot of variety within those archetypes. Characters get to keep skills and Arts from unlocked and mastered classes which allows for a very rewarding and layered sense of progression, and the amount of versatility the system offers is quite impressive. There are technically no limits to what your characters can multiclass to, apart from how fast they can unlock it (which depends on their compatibility with that class), but I like that there are still some classes some characters are better at (thanks to their stat spread, if nothing else), since this makes the party feel less uniform and also rewards prioritizing which classes to rank up in. It's also worth mentioning that the support classes (especially the healers) have gotten some love in terms of making them more fun to play.
While this game has some of the best party-building of any jRPG that I have played (it's up there with XBCX), I do have a couple of nitpicks on that front. First, the way the classes are inherited and unlocked is kinda borked. The inheritors sometimes seem to make no sense gameplay-wise, probably because they are determined by the story. But sometimes even the compatibility seems wrong, like Lanz being slower to get Lost Vanguard (one of his best classes) than Noah. The fact that you unlock and rank up classes at a slower rate if you are overleveled is something I also have mixed feelings about. On the other hand, it's not a bad way of tuning things so that they don't become too easy, but on the other it seems a bit too punitive, especially since it seems to be rather easy to become overleveled, even if you don't use the extra levels (there are after all, a lot of unique and optional bosses to do, not to mention side content). I guess this is something I'll make my mind on in future plays.
Second, the accessory system means that we don't get classes like those of XBCX that had classes that used multiple weapons. Full Metal Jaguar is a lot of fun in this game, but I kinda miss the old FMJ from XBCX that allowed you to switch from dual pistols to dual swords. A FMJ in Xenoblade 3 still should have access to Arts from other classes to add some variety, but it's not quite the same. Don't get me wrong, in some ways it's still better than in X due to the improved combat mechanics (many of which came from 2), but when it comes to the fun of using a particular class, 3 sometimes feels more like a sidegrade than the upgrade it should be, in relation to X. On the plus side, you can now change your party members' classes, so that's a clear improvement over X. Then again, X had the better itemization and equipment system. X is definitely the main competitor to 3 on the character building front generally, and I expected this game to be similar but inferior to it in that regard when I came into it. However, I think now that they are both roughly similar in terms of charbuilding, 3 is a step forward in some ways and a step back in others. Personally, I'm a big fan of big party sizes and full customization, so I'm a bit partial to 3 when it comes to this aspect. That said, I do miss Samurai Gunner, and this game really needs X-style Assault Rifles. And no, the War Medic's weapon won't cut it.
-The combat is also a highlight of the game. I feel the system itself has a step back from 2 in terms of complexity thanks to the elimination of the elemental orb/burst mechanic, but it's great that they've kept the Art and auto-attack canceling mechanics. The combo system got reworked a bit and now you can choose, after toppling, whether to do a Smash combo (Launch and Smash) or a Burst combo (Daze and Burst). I kinda like this, as it gives you the choice between more damage and utility. As I said above, the fact that the support classes are more fun to play also helps, since the new system seems to have replaced the systemic complexity of 2 with party management during combat. You can switch freely between characters during combat, and when the game is at its hardest it feels very rewarding to switch around and take actions with different characters in a tactical way. I will say though, that the actual switching controls are kinda clunky. I'm not a big fan of radial menus, but even that would be an improvement to cycling through the characters the way you gotta do it now. I hope this gets addressed eventually (though I'm not too optimistic).
It's debatable whether the combat is better than 2's, as that one could reach quite a bit of complexity with its Blade setups and elemental orb system, but you could probably argue that the combat here is better than X's in most respects. The one exception may be the mech combat, as that was more spectacular back in X, though I will say that in 3 it at least feels better integrated with the normal combat, which can also be considered a point against it, I suppose, as most fights in 3 assume you are using Ouroboros after a certain point.
-I won't say too much about the exploration not because it isn't good, but because this post is already long enough, heh. I think the most important takeaway here is that this is probably the one gameplay area where I think 3 is noticeably worse than 2 and X. 2 could cause some frustration due to the way field skills were handled, but I feel that its areas were more involved in terms of design, with more interesting nooks and crannies, optional paths and whatnot. X, meanwhile, had pretty much the best exploration of these three, and I don't really think 3 touches it here. Ultimately though, the areas are fine, just not up to par with previous games. There is plenty of biome variety, from a sunny archipelago to snowy mountains to a desert to ruined settlements reclaimed by the forest. And the areas are dotted with plenty of interesting optional encounters (some very hard) along with that rewards that are worthwhile to your progression.
-The music is definitely a high point of the game. Lots of different bangers for diverse combat situations and some atmospheric tracks during exploration.
There has been a lot of hype surrounding this game and a lot of people have been proclaiming it the best in the series. I don't think this game stands head and shoulders above 2 and X at all. All of these games have their pros and their cons. It's interesting how the games in this series can be so different from each other to almost feel incommensurable while at the same time having obvious throughlines uniting them. I'd say all of them are at about a similar level of quality, it just depends on which aspect the player enjoys most. As a fan of RPGs that emphasize large fully-customizable parties, multiclassing systems and combat with greater emphasis on role-synergies, I can't help but to have a soft spot for XBC3, even if I wouldn't go as far as calling it the best. Regardless of where one ranks this game in its series though, it's definitely a great JRPG.