Oooo. This sounds like fun!
I'm thinking I'd like to go with a gishy fear build, something like Illithid 7/Paladin of Tyranny 3//Dread Necromancer 4/Dread Witch 5/Dread Necromancer +1 (5); and then taking the final level of Illithid followed by maybe Crusader on the one side, and Dread Necromancer on the other.
Roll for stats:
Okay, question. Can I be a Necropolitan despite the fact that the template only allows for humanoids?