Demonic your thinking in your current Mir 3 terms (eg Mobs cannot cross maps like players,, why cant i put this in my server??)
yeah the mobs could have the town name above their name.
the guilds could own as many towns as they wanted, however, if the server felt it was getting unbalanced (eg, all the high level players in the guild that has all the towns) it would launch a massive invasion to destroy all 3 towns, bringing down the players level, and them loosing items (i see no reason why mobs should not be allowed to wear jewellery - apart from 56k modems)
basically, dont think about what can already be done with your server, this is not your server, it has no limits.
oh, and Milo? - i hardly ever finish anything! :P