I have played the whole first part of the game with Nalia as my thief. True, you're gonna need Knock. But you don't need that creep, Yoshimo, if you don't want him. P.S. Just let Minsc kill Edwin, and take his amulet and give it to Nalia.
Mitro, I don't often disagree with you, but Viconia with a strength belt, is better than Jah likewise, due to her better DEX