Let me preface this that I don't want complete customization for characters. Yet there should be more than there is now. There's only 5 companions right not and while I know there will be more coming I doubt it's gonna be that much more.
BG1 and BG2 at least gave you so many options that customization was not really necessary. Yet right now there's a bit of an issue where you have to take certain characters along for your party to be viable unless you fill that role yourself. In particular those are Shadowheart to be the healer and Lae'zel as your warrior/tank. But what if you don't like any of them.
My idea is that there should be an optional way for the player to change this around somewhat, either at the start of the game alongside "Who do you dream of at night" or when/just before you meet the companion(like with D:OS 2).
The extra options per companion should reflect realistic alternatives for them like
Shadowheart: Rogue or Wizard
Lae'zel: Wizard or Monk
Astarion: Fighter or Bard
Wyll: Fighter, Ranger or Rogue
Gale's backstory is pretty much all about the fact that he's a Wizard so I guess he could only feasibly be a Sorcerer or Warlock
