There should be a setting for Diplomat. If on, this would make combat vehicles 3 times as expensive, making it very costly to build huge armies. The result would be a game revolving around good management of resources rather than "who has more tanks". This would be especially good for Space Race, where you can make deals, like telling the players who are a ways behind "I'll give you an Ion Drive Module, if you send me 2000 rare" or something. You can still build vehicles, but you have to be far more careful with them, and not just throw them at the other guy wantonly.