When it comes to UI and party controls, I think BG3's problem is that Larian hasn't designed them for a D&D CRPG, they've just tried to adapt the UI and controls from Original Sin, and those aren't adequate. They need to go back to the drawing board on this stuff and re-design after looking at how other D&D and D&D adjacent CRPGs have have handled turning D&D into a playable, understandable video game. Players need all the information that would be on their tabletop character sheet surfaced and at their fingertips with breakdowns for folks who aren't familiar with 5e. They also need to be able to quickly and easily manage a party of four characters, both moving them around the map and sorting/using their various abilities and items. This whole game feels like a D&D mod for Original Sin 2, not a game designed from the ground up to be Baldur's Gate 3.
