Need to add more #-of-player options to each map/game type. Seems to be just 2 or 4 players. Should be able to have 3, 5, 6,etc players to each game type.
Another big thing would be adding more move-times. e.g. 10 mins., 1 hour, 6 hour, etc. Getting stuck in a game where one player waits 24hrs every turn sucks.
I think if you add more variety to the basic games you might attract more people to stay & play. I would pay to have more options, but there are only about 10-12 people actually playing so it's not worth paying if you can't even fill a 4 person game.