I´d been watching the above maniacal endless stream on and off and, even when taking into account differences between backseat gaming and actually playing and likeliness of being a bit biased because I don´t have PS4, at least the PvE portion of the game seemed surprisingly underwhelming to me.
As a fan of both Dark Souls games, the only aspects I´ve found consistently solid were art direction and level design, though not without caveats - after the central city parts the exteriors started to feel aesthetically somewhat monotonous (including a fair amount of grey-ish stuff a bit á la Harvest Valley or Huntman´s Copse) and level design didn´t seem to bring anything new interesting to the table (the areas seemed more labyrinthine and with more shortcuts than DS2´s on average, but also felt quite formulaic, without interactive options á la Pharros lockstones or shortcuts made by blowing stuff up - just a lot of doors which "open from other side" and elevators activated from one side).
Other than that I think the sentiment this game is bare bones compared to Souls games is quite spot on, certainly so when it comes to "RPG elements".
The amount of weapons has been drastically decreased and I don´t think the fact they´re now more unique makes up for it, especially since off hand is exclusively for guns and options like dual wielding and two handing are tied to few specific weapons´ transformations.
Same goes for outfits, except these also happen to lack in the uniqueness department, both aesthetically and mechanically (considering equipment load being out and one rolling speed/length for all).
Most of the weapons also have requirements low to the point of meaninglessness.
The above is also connected to what seemed like probably the biggest negative difference to me - the exploration rarely seemed rewarding - vast majority of loot (both from enemies and environment) comprises of vials/bullets and upgrade materials, anything else being (very) few and far between. There´s an occasional outfit or equivalent of Souls´ rings (with seemingly less variety) and some enemies, mostly bosses, drop a token which makes the homebase´s merchant sell a new weapon and that´s pretty much it.
Speaking of merchants, and NPCs in general, the game seemed a lot more bare bones in this regard as well - AFAICT there´s only one merchant in the whole game and he/it doesn´t talk, and after the earlier portions of the game the encounters with talkative NPCs seemed really rare (and even in the earlier game most of the speaking characters seemed to be just voices behind locked doors).
The lack of talks and loot also created an impression that there´s less lore bits in general. There are also notes scattered throughout the environment, but, once again, there didn´t seem to be much of these either.
I´m guessing the NPC/lore stuff will improve on more thorough playthroughs, partially also because there did seem to be hints at storylines one can uncover when being at the right time at the right spot (not something I´m personally
that fond of, but still) and there also might be secrets revealed for those using/wearing right items, or even gestures, at appropriate circumstances (which would be cool).
It´s also possible some NPCs will "come alive" when online.
In general though, I´d be surprised if the game ends up feeling richer in these regards.
I also don´t think the healing consumables system was a good decision. Exploring or fighting bosses with 20+ vials in pack is likely to make the resource aspect non-issue for decent players and at the same time it may make the game unnecessarily tedious for newcomers and/or people struggling with some parts of the game, because the only way to obtain the pots is to grind.
Considering the regain mechanics, I think the system from DS1 would be more appropriate (say, 10 vials on respawn/death, without enemies dropping any).
Finally, I think the new dodge available only when locked-on might exacerbate camera issues some of the bigger bosses seem to come with.
When trying to put the preconception of Bloodborne being a Souls game aside, the stream still created an impression the game features what I´d consider significant flaws on its own.
The biggest mechanical issue seemed to be that for a lot of the time the enemies weren´t appropriately designed to counter players´ combat arsenal. The first 1/3 of the game or so seemed alright in this regard, but afterward almost everything felt like it wasn´t designed with the new combat system in mind, pretty much the only exceptions being fighting NPCs á la Souls´ invaders (though apparently without AI improvements introduced in DS2´s DLCs). The most notable cases being mid-to-late game bosses who were mostly slow, with few moves, and/or lack of countermeasures to gun parries. For some reason the game also features a fair amount of fodder enemies slowly crawling on the ground and enemies who are entirely harmless except for a single grab attack which can deplete most, or all, HP in one attack, neither of which I consider interesting design.
The streamer was able to brute force through pretty much all of the mid/late game, rarely breaking a sweat, killed all bosses in 1-2 tries, was not "overlevelled" (unless I´ve missed some extensive grinding session) and didn´t seem like a particularly skilled player either.
The biggest general issue to me was that the last 2/3 of the game seemed relatively uninspired across the board, except perhaps for art direction.
The early game felt more fleshed out in terms of NPC interactivity, level design, variety of common enemies (which also felt to fight appropriately considering low level gameplay) and the bosses felt well designed with the new combat system in mind (relentless and with solid arsenal of moves), but most of what came afterwards gave a strong impression of being unfinished, not particularly well thought-out and creatively lacking (bar some of the art).
I know that not all bosses can be 100% keepers, but whereas in the previous games the quality was fairly spread out throughout, in this game all highlights seem to be featured within first 4-5, unless the few bosses the streamer hasn´t fought are return to form.
I think quality-wise both vanilla Dark Souls games were somewhat frontloaded, but in the case of Bloodborne the differences feel a lot more pronounced, structurally more obvious and the drop comes earlier.
Hopefully the online aspect will turn out fun and/or the early patching will bring some major PvE improvements.
If not, I expect a major uproar once people get to the latter portions of the game, unless the stream was somehow seriously misleading
or I let my inability to play the game myself get the better of me when forming my impressions.
But I thought BB was made by A-Team?
Based on the above admittedly possibly misguided impressions, I´d say A-Team was busy making DS2 DLCs.