If your going that route why not just suggest the developers do the whole wow gear score route? at least you know they arent geared gimp, says nothing for skill level.
I can understand not wanting to adhoc with gimps, and alot of people may still adhoc despite having an endgame shell, i often do so as the current focus may not always fall in line with the stuff im working towards, in which case i gather people together to get it done on my own.
Either way as its been said it'd be no different then the mentor flag, unless there was some formal system in place to allow you to flag H, even if they could come up with a way to determine those worthy of using the H flag im sure it would be incomplete, like wow gear scores, it only evaluates the players ability to loot whore and not their actual level of skill. further more such a system would only divide the player base in a very vehement way.
