I"m not sure about that. It's realy awesome to build an RFC mod on it. But if you want any other type of mod (like a Game of Thrones themed mod), I wouldn't use it. It's not designed for that. Unless you want the RFC features in that mod ofcourse.
well of course. it would be a game of thrones rfc mod. uhvs, dynamic spawns, etc
at the start you can only play as the first men,(with the children of the forest on the board as natives)
the andals appear on teh board first as seljuk/mongol like waves of barbarians, and then settle as kingdoms, flipping the barb conquered cities. the lannisters, arryns, ironborn, spawn around then (not sure when the starks spawn as a separate entity from the generic first men,)
later on the rhoynar make a similar barb invasion then the martells spawn in dorne.
eventually the targaryens show up as a nonplayable civ. (im not sure how this would be handled, perhaps they could be encouraged to vassalize a lot) but their auto stacks should encourage them to conquer the stormlands riverlands and reach, upon which the tully, tyrell and baratheon spawns would trigger, flipping the targ or old civ landss appropriately.
theres a ton of other features that could make it better, i was just thinking of the basic structure
eta: anyways, just a suggestion. other fictional worlds with long histories could be ideas for mods as well.
it was the waves of invasion that made me think of it. RFC: british isles would be interesting as well