Hehe, never had Aerie for longer than a few days. Minsc is good/funny but not essencial. There are other/ better figthers. Valygar have katanas, Keldorn is useful. I like Viconia, but Anomen is better for front line (two times more HP). But if you have Jaheira and Minsc/Valygar you have already two good front line guys. One an consider Mazzy, and if you want to lead your party take same class with more HP and you don need to care for Anomen.
Aerie - there are a lot of dreamers here who want to restore her wings and so on. She is useful at the beginning, later she is far far away with levels. She will be your weak spot untill she will gain higher level spells in the middle of ToB (and abilities). (Similarly with other multiclass NPCs, but Jaheira can got all druid is able to get in SoA and Jan is half theif (and very funny), so I would keep him, unless you will play thief.)
Zbyszek
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Well known expetitioner, Heffalumps hunter, friend of Boo.