Is there anyway you can mod Imperium levels so that different factions have different levels?

For example I want to generate a faction, lets call it 'Horde', up against another faction - 'Elite'.

Rather than just limit Elite factions to having smaller unit sizes, and Horde larger, I'd like to have Horde to be able to field more armies per Imperium level, possibly tied to the strength of the leader - can you increase Fame via Trait?

PS - is there a trait editing tutorial out there anywhere? I'm not such a fan of the art style of TTT, so I've purposefully stayed away from it - I've gotten used to the vanilla style of art, but would appreciate reading through a tutorial on how to edit traits.