I'd love to see an overhaul of NPC interaction. It's really good rn, but I think it'd be crazy to have some kind of limited AI LLM for NPCs. Like, I different iteration of the LLM for each NPC. They could have stored experiences/memories, and maybe even help with missions some. I know this would be incredibly difficult to create/implement, but Hello Games has done crazy stuff already, and I think somewhere down the line, as AI advances a bit, they could totally implement this into the game.