The world is your oyster my friend. You’ll need to cover a Thief first and they are plentiful. Imoen for pure or for a dual-classed Mage and Montaron are available straight away. Monty can cover archery or melee, he’s great and easily customisable.

Next is Arcane magic. Xar is available straight up. Give him a time of Wisdom and you can even get an extremely powerful Mage/Cleric dual. Edwin for pure, Can for a sick looking sword and the most OP Sleep spells that will instantly win you half the game. Want pew pew? Dynaheir awaits.

Divine time. Viconia can be grabbed straight up, Branwen is ready and waiting. Both are good, Viconia with slings and Branwen with Ashideena. Want Druid spells? Well Jaheira is it until Faldorn and boy is Faldorn underrated in EE. She’ll net you the only level 5 spells you can get and a sick wolf. Need another tank? My boy Yeslick got you covered.

Melee. Kagain will throw down with you all day. Ajantis will too, ‘yeah!’. Khalid is solid and can go archery if you want. Shar-Teel will wreck face and if you want will backstab better than anyone once dualled.

Archers, Clint Eastwood Kivan and Coran will shoot almost anything to death before it even gets to you to tank.

I’d say pick alignments and settle on how many NPCs you want total. You could literally use only Monty and dualled Xar and cover everything you mentioned.