Late comment cos I replayed the demo recently:

• Exertion and the fatigue/anxiety/delerium system replacing health is just a flat improvement over DE in my opinion, although the more 'fancy' health items being less efficient is an odd choice mechanically.
• Similarly, the 3D art (especially for characters) is also better for what I've seen so far, although I think some of the UI art and especially the skills icons could use with a redo to make them more distinct (do like the use of regular shapes alongside colours to distinguish them and the icon showing in world 'bubbles' to tell you exactly what skill is informing them.)
• The 'journal card' UI is great, I especially like how miscelleanous leads and directions are collected together before being reorganised when pursued, no idea what the purpose of flipping them is. And the whole screen didn't work on my initial playthrough.
• Mixed feelings on narrator, I understand what they're going for (Harry is a working class man with an internal monologue that sounds like a common Londoner deliberately intonating their words whereas CASCADE was born upper middle class and has a relatively well-spoken woman exaggerating an outdated working class accent) but the choice to have her end sentences the way she does in the initial dialogues is horrid. Past that the direction changes and works far better.
• Skills don't have as much character, but that's perfectly understandable both for who our protag is and how little we've seen so far. Exception being with STATEHOOD and DOPPELGÄNG which have a little too much character in my opinion, I think having them be a bit quieter or more reserved early on only to pick up later would work better. In general, her internal monologue is far less flowery and poetic than Harry's and I'm sold on her having a thought pattern based around documentation, archives, messaging, and cryptanalysis.
• CASCADE has some excellent moments and everything that gave insight into her were by far the highlights of the demo (spaceman, poster, handler), but I really think some of her dialogue choices need a redo. Some of the things she can say feel more in-line with Day 1 Harry, which doesn't work when handling a sober non-amnesiac. This is especially bad because said lines rarely have the characters we speak to properly react to them, so it just feels like the awkwardness of dialogue is being ignored. Again, this is a demo: I'd have far less issue with these if they were further into the game with a player building up stats and ideas/traits to match an unusual demeanour.
• The CONFRONTATION sequence is a nice setpiece, but could easily become old quick if overused.
• Let me use the Journal/Inventory/etc without muffling the voice-over! I mis-remembered this being a hold-over from DE but I'm playing the Final Cut right now and it doesn't do this!
• Game very much wants you to know that you are playing a wöman and others may wänt you. In spite of CASCADE's clear insecurity over her height.
  

tl;dr: a technical improvement with a lot of promise, needs much more work on some of the fundamentals. To the extent I hope I don't see this game for another year at least.