Player inactivity is a serious problem

Player inactivity kills all the fun. This problem can easily be solved by having 10-15% of matches accessible and visible only to active players. You figure out who is active by having some sort of activity score. Quitting a match really hurts activity score the variables are when you quit and how many homeland cities you have at the moment of quitting. quitting too many matches will result in these matches of active players invisible to you. These matches will be invisible to new players as well. Additionally, you don't even need to show which matches are meant for active players. It will just invisibly boost the fun.

I'm not saying this is the exact way it should be done. But it's an idea. This wouldn't hurt neither the game nor the players, and would create space for actually active players to play together. Otherwise every match is 10-15 countries (if we are being generous) against bunch of AI countries.