I think there is a viable marketing model that somebody smart will take advantage of. However, who and when?
DEVELOP A UNIVERSAL GAME EDITOR flavored Civ model or another.
Sell 100 US dollars with built-in sub-licensing.
Establish easy to follow criteria, such as mininum hours of play-testing etc.
Include graphics generator and easy change default graphics of all kinds.
Put each MOD on market for $9.95 with some kind of split.
Calmly proceed to sell hundreds of different mods as stand-alone games.
Let them age in the market a few months, collect them into like batches and resell 3-5 of these stand-alones for same price $9.95.
Excepting the 'hot ones' (mods as stand-alone games) feed the name of the modder as new sub-brand and produce some more.
Many people get richer but root company who develops, supports and sub-licienses the Universal Game Editor will make the most for a decade.
For more details on this idea contact me anytime.
Antrine