"A HM concepts a skill/spell/item, the wizard codes the skill/spell/item, it is approved, and becomes the focus for some quest that the HM completes in order to obtain the skill/spell/ability."

A bit too arbitrary I feel. It would be so much up to luck whether an arch feels like doing it... Almost like a whim.

"Worshipper Recruitment - I'd envision this as a jump-off point for a piety system for gods. HMs could recruit/convert mortals to their god's cause, and the HM would gain powers/abilities (think reduction of DC for followers, "ritual blessings" of present worshippers, special hit chances, special protection chances, instant-rez on death) for those who choose their worship and attribute it to the HM."

We... had.... demigods....