I've often pondered the idea of starting a mod that includes all the fronts and covers the whole timeline. I'm working on the tech trees right now, the only problem is that I have absolutely no modding experience.
Atm several players have crashes with EF and soviets, we expect this rises when OH and campaigns are released, due to the amount of units. We will try to optimize the units we make as much as we can, but this certainly is a burden for players who just want to play the mod and for those who want like ten factions in CoH.