Custom Factions in Multiplayer?

Never going to happen, too easy to modify the custom faction for all kind of cheese. There's a reason the MP files are separate from SP files, that's to preserve fairness.

Aw that's a shame. Maybe they could include an option for playing with trusted opponents (ie. friends)? Is this something that could be modded into multiplayer perhaps?

I'm guessing that custom sovereigns aren't allowed either?  That also saddens me   There's gotta be a way to include these in custom games...

They should simply have the ability to have custom factions/sovereigns, and after the initial save to your hard drive is done, do like VAC does and check whether or not the files have been modified since initial creation. Of course, I have no idea how big a drain on resources this would be to Stardock, so for the moment, no custom factions/sovereigns is fair.

Do a validity check on customs on new game to make sure they match the rules of creation? After that the data should be stored in the saves. If you can modify the save data in any way then it wouldn't matter if it was custom or not. 

Everyone just play Ythril (: 

Anyway, custom sovs and custom factions won't be in for a longggg time.