The Inquisitor freebie true sight
is very nice, but the dispel magic is limited, since it's such a two-edged sword. I always end up dispelling party buffs with it, but maybe that's just because I'm uncoordinated
In any case, giving up all the spells + lay hands + immunity to level drain for that seems like a poor tradeoff to me.
The points about using pre-existing NPCs are good, too, unless you don't like banter.
PS - give Viconia a kit - Talos suits her personality well, but Helm includes True sight - or you can always tweak her special abilities directly.