In today's positionless game, I think that at the very least we ought to be able to edit a player's position on the fly. I don't believe that has any effect in-game but sometimes you get a Ben Simmons and you decide you'd rather use him at PF than PG and you just have to kind of remember where he plays now year after year. I'd love to be able to switch positions around without going into the player editor.

Also, as a stretch goal, since this would require you to (hopefully only) update a table in the database or (hopefully not!) update some hardcoded values, I'd like to be able to add:

G - guys who play 1/2
GF - 2/3s, a really, really common position nowadays, especially for rotational players (but also a lot of starters flip between 2 and 3 a ton)
F - for your classic James Worthy or Grant Hill style combo forwards, guys who you give minutes to at both the 3 and the 4
FC - for general big men (4/5)