Its really fun to make characters and it would be nice to have a separate character building option so you can make characters in advance or just play around with building them.
I don't expect this to be a thing this early but it would be cool in the finished game since I'd probably be using BG3 for making one shot characters since its so fast and easy.
Probably the coolist thing would be (if WotC allow it) would be to put options from later books in. Even if they're not in the main game having more options there could make it a great tool for players.
Another idea would be to allow you to level up characters so you can make higher level characters (since many one shots are level 3-5 or 10) or to test how your character would be at higher levels or to preview features.
