I'd be fine if it was xp that could ONLY be used to improve administrator levels. But as it stands now, there's little reason to EVER put heroes in towns.

IMO admin heroes are a small niche. you may pick up one guy and make him an admin so your main fortress doesn't suffer reduced production from unrest or something, but other than that, they aren't a big focus in my games. while you're at it, you may as well give him road building so he can do something useful when you don't need the unrest dump. it's not terribly hard to give them a few level ups and they generally only make it to level 5 or something. going for merchant or lore seems like a waste. if i have access to spellbooks, i may use them on an admin hero to level up a spell school (for the strategic spells/buffs) i otherwise won't get, since they are low level and their other traits aren't worth the trouble later in the game anyway. in this case, you may also pick up admin 3 at level 8 for a little global unrest reduction.

don't think the game really needs a separate XP system for those utility guys. just lend them a small army for a few seasons, kill some darklings or wolves, get them to admin 2 and road building and be done with it.

yeah i agree that removing them entirely wouldn't really break the game. maybe the game would be better off with a pure commander that doesn't share a path with the admin. the commander is pretty decent, but since it's really just one straight line, it might be more interesting to have more options for them.