The biggest problem with making CIS/Clone factions is the lack of .mesh files (the ships' digital models). All of the ships used in Requiem had been ripped by Jason from various sources.
Making such a model is:
a) time consuming (as in, model a month is fucking fast)
b) pain in the ass (various possible bugs, discrepancies etc)
bonus: Jason works in .xsi and Rebellion accepts .mesh, with there being no converter from one to the other.
I'm with you on the epicness of the idea, but it's simply impossible to do now, unless you're willing to create the models / textures.
Hope that answered you