I am not a RUS modder, I am pretty bad at modding in general, but I am just throwing an idea of something I would love to see, even though, of course, 100% of the actual work needed would have to be done by somewhat who is not me (for now - once I stop postponing my Natchez mod, I may try it - but given it looks extremely complex I won't go beyond).
It would be a RUS Grand Campaign where each vaguely significant faction (except Green) and even some subfactions (Finland / Balts / ...) would be playable by a player from the very moment they appear.
For instance, a Grand Campaign starts normally with the Red, the Southern White (including Don) and the Siberian White (so 3 players). Northern and/or Northerwestern white appear - a new player is called - now it is a 4 players games. Anarchist sub-faction appears, a new player is called - now it is a 5 player games. Baltic states activate - 6 player games. Anarchists fumble and are wiped out - 5 players game again. Then Finland, then Poland...
At to this all the interesting factions created by the Fatal Year mods : Baltic Germans for instance...
Basically, the "minor" players would have to be content with their limited objectives, but as far as I concerne playing Anarchist, Balts or Finland "only" is not a problem. After all, playing Sertorius in AJE is only playing in Spain.
That would make outstanding AAR, fun negotiation, and generally speaking a lot of lulz...