I'm not fond of some of the classes or play as one myself and want else on companions, but I try to keep them lore friendly.
- Shadowhear I first made a monk, on 2nd playthrough first a paladin, but changed her to a Fighter eventually and I love the positive battle impact.
- Halsin I changed to a Bear Heart Barbarian. I'm not fond of Druids in fights, not sure why.
- Wyll I always respec, also not fond of Warlocs. He usually ends up a paladin, but I also usually don't bring him along.
- Karlach I made a ranger.
- Astarion also a ranger.
- Gale I keep a wizard, because I cannot find any lore friendly class other than a wizard and also tbh I don't mind wizards at all.
- Made Lae'Zel a Vlakith cleric.
- I'd respect Jaheira, but I cannot bear the fake sounding accent, so I don't bring her anywhere.
It's like 50/50 for me if they fail when they don't have performance. But if you're that set on it you can take the actor feat which gives performance proficiency.