Leadership and Mobs

[Ruethgar]

So I have been optimizing my E6 Leadership. My DM allows the feat, and allows the followers to be customized(apart from templates and obscure power-hungry races), but requires they all be NPC classes. With the massive number of followers who are combat able, I was wondering how powerful it would be to just make them all mobs? It would mostly be for efficiency, a few mobs attacking is easier to deal with than 300 peasants and although they may deal more consistent damage than they would otherwise, they are also a lot less versatile in that form.

As a side note, if a mob gathers together out of anger and then contracts festering hate, should the time limit of mobs apply?