My husband sent Irving, the first enchanter. He was level 16 (compared to my husband's party of 12-13 at the time) and had, if I recall, mediocre spells. I think he had all of the lightning spells and a lot of healing/spirit spells but no entropy spells. He was also maxed in the arcane spell line but didn't have, and couldn't pick, a specialization. Maybe your coercion has to be high enough to convince him to go. Also, you don't have access to your party's inventory if you send him, so you can't use potions, etc.