Haven't come across anything as bad as Hexen 1's switch hunting so far. The game works similarly to Hexen with the hub areas where various portals must be unlocked to travel to different maps, and you've got to keep coming back to the hub to bring newfound keys and items, but there's none of Hexen's "one ninth of the bullshit nightmare puzzle has been completed" crap with switches hidden in the most obtuse locations.
Most of the puzzles are about navigation, like, the object/key/switch you need to reach is usually fairly clearly visible and the challenge is to figure out how to get up to it. After you get your shapeshifting abilities, the puzzles become more Metroidvania-y. For example, you reach a huge pool of lava that kills you when you walk on it, but you can see a key on the other side so you know there must be a way across. A bit later in another map, you find a Demon form power-up which allows you to walk across lava unharmed, so you know to travel back to the lava pit from earlier which you can now cross. Another example, you see various cracked walls in the first episode. Later, you get the Golem form, and the game tells you that it can punch through cracked walls, so you know to go back to the janky walls you saw earlier to smash through them to access new areas. Stuff like that.
There's also an objectives screen that really helps by telling you which map you should be searching in, plus a hint of what to do. Basically, imagine Hexen 2 with somewhat more intuitive map design, and the game giving you reasonably clear hints on what to do next. And much better combat.
The only real problem I had so far was navigating E1's hub area, which is a little bit sprawling to the point where it can be tricky to remember where the portals to each map are, but it's not too bad. The demo is pretty lengthy, I think it's the whole first episode, so you can get a thorough feel of the game from that.
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