[Sol]

I can tell you this much.
My first time through the game I played with a druid(avenger), viconia, cernd, and jaheira. Finishing up the game, I ended in ToB at just about 5k below epic level (I hit epic level before (very minor spoiler)gromnir). I hard no truly hard time finishing anything. I would imagine a duo game to be fun, especially if you make two self created characters. I think I would take a thief/cleric multi and a bard(blade) for a little spellcasting, traps, and cleric spells. Just about everything you need in two nice little neat packages.

spoilerish/tacticish note: I never did fight kangaxx or the twisted rune, but spellcasting foes were relatively simple to take out because protection from magic weapons was handled by sword spider form, and spellcasting was easily defeated by insect plague and later on creeping doom, coupled with a doom if neccesary