Very interesting insight into the AI generation process for this game. Hopefully clarifying the effort involved will temper some of the arguments that using AI necessarily equates laziness. (probably not, but it would be nice)
I'm not going to focus too much on this because I think I, at least to some extent, made my point in the original comment, but if a static image or background works for a particular scene, just use it. I think if you get caught up in making animations for everything whether the scene needs it or not you might end up burning out. Sometimes it's okay to work smarter, not harder.
I understand what you're going for with the "blank slate protagonist" thing, and to that I have a couple comments:
1. While this concept works sometimes (Twilight is probably the most notoriously commercially successful one, but that's an... undesirable comp so let's throw out another FVN like Adastra), character motivation, reactions to scenes, and agency is still important. Maybe another way of looking at it is there's a difference between leaving things open for players to graft motivations or characteristics to and having the MC do things that practically no player would do without explanation.
2. I don't think you should necessarily be averse to providing a more concrete MC in general. Not necessarily saying you need to go into super deep detail about his background or anything, but I think people may connect more with defined protagonists than you might think. People will find similarities to latch onto, which can often be more powerful than trying to paste your personality onto a blank slate.
It's your story at the end of the day though. One of the best parts of creative writing is that there's no answer key; I think there are plenty of ways you can make this story work.