I've been playing with the lands of conquer mod 3.1 ( last non expansion version ) and the creator of the mod did an excellent job of creating well balance faction stacks including the rebel stacks. I also like the mod because it only enhances the vanilla game experience without adding more factions/more units. I have read the Stainless Steel mod and Burning Crusade mods are equally enjoyable but I have yet to played those mods.