I'm happy with the idea of population caps. Sure, it's not an ideal way of doing things, but it sure beats the inevitable "tank rush" so familiar to anyone who ever played for example Red Alert. Without the pop cap all you have to do is turtle until you have a huge army, then attack-move them in the direction of the enemy base and go make yourself a cup of tea while your opponent is swarmed.
I almost never play any games online, so having someone drop out of the game and leave me alone is not something I have to worry about. Sure, I can see it being a problem as of course it would mean virtually an automatic victory for the other side.
It would be great if there was a way to implement tactical considerations that would render the concept of pop cap obsolete, but I don't think there is one. A lot of games boast of their superior tactical playability, but in truth there are no games out there that cannot be won by having a huge army of the most powerful unit in the game, regardless of tactical skill. So until someone comes up with an inspired idea, the pop cap is in my opinion the best way of ensuring at least a fair fight.
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