1. HMs may be allowed to train some unique spells/skills related to their guild. Make few to choice from, but you can train only 1 from the list.
I still like this idea a lot. Especially the part of choosing only one from a list - seems to make a specialized character to me (a necromancer who specializes in improving pets over making them, a tinker who specializes in armour forging rather than runes, a nightblade who specializes in poison rather than distance spells, a chaotic-lord who specializes in... uhh... puppy kicking?)