Alright, I here a lot of bitching that Credits is the end-all, be-all resource...with it, you can get anything. This is why some see TEC as uber and Vasari as gimped
I am here to demonstrate why this is wrong. Anyone ever see the "Offer amount" button in the market screen? Yeah, it does something, and it does something wonderful.
USE THE "OFFER AMOUNT" buttons! Don't waste your time selling your metal/crystal the normal way unless everyone has plenty of it (e.g. a map with 2048624642 volcanic planets). When you use the "Offer amount" button, any player who wants to buy that resource will have to buy it from you before buying it from the game.
What's this mean? If a Vasari player and a TEC player are facing off, the TEC player needs to give his hard-earned credits to the Vasari player in order to get that much-needed crystal/metal. It essentially means that the Vasari player is selling his resources at rates even higher than 1.2, courtesy of the TEC player.
The only way this would not work is if everyone else in the game completely avoided buying metal/crystal on the market, in which case you're at an advantage anyway.