Okay, finished the demo and here are my final thoughts on it:
Visuals are nice - the game looks good overall. I played on graphics mode and encountered no real problems until the panzer dragoon portion at the end - there was some serious frame drops that even I noticed and I don't much care for frame rate, it was a bit jarring. I was surprised this was happening, I feel like the Ps5 should have been capable of what was on screen (two characters, some random pillars/infrastructure and generic abyss elsewise). But in general I like the animations, visual design, etc. It looks pretty good.
Plot seems interesting enough, the rogue element was a little heavy on the telegraphing I think, but fine and interested to see where things go from here.
Combat is OK. I strongly prefer FF VII remake combat best I can tell at the moment. I don't like that there is no resource consumption for magical attacks and instead we have summon-based cooldown abilities to swap around through. It isn't the end of the world and maybe it'll turn out just fine. I only peeked lightly into the battle aspect of the demo because I didn't want to jump far ahead in the plot, but I did a few battles and got my mind wrapped around it. I didn't find any of the encounters in the main portion of the demo to be challenging at all, it seems very easy to dodge or be out of the way of enemy attacks when they come and the repetition of just slowly chugging away at the stagger bar to do damage is a little boring, but I'm sure as the game goes on I'll have other abilities that make stagger easier to achieve depending on the enemy you are fighting, so I'm really not worried about that in the long run, just for the demo purposes it was a bit bland and unchallenging. As I've said before, FF is not known for difficulty, so I can't really hold it against it. I like potions being limited, but I didn't really have to use a potion the whole time, so I'm not sure how much value that adds to the strategy - I'm sure it will be more important later, but for the demo it's a non factor. Kills desire to explore what little there is to explore when you just find another potion that's automatically consumed because you already have too many. I worry strongly there will be very little exploration going on in the full game.
I don't really see the point of the big Eikon setpiece battles though - I think these would have been better left to cutscenes. Pressing triangle for 5 minutes while occasionally dodging did absolutely nothing for me and it wasn't even much of a visual spectacle as half was down a repetitive tunnel and the other was in a non-descript area of columns. I could do without it but I'm sure there will be some interesting happenings with it at certain points in the game that are cool.
I'm not excited about just clicking points on a map and going to those zones, I'd at least like something along the lines of FF X where there are zones between major areas, but I'm sure this will be better than it seems in the full game.
I really like the musical score quite a lot - hoping that it continues to be pretty excellent.
Overall I still want to play it, but not as hype as I had hoped for me personally.