I am heavily in favor of the system prior to Reach. You should earn what you get. If credits are still somehow part of the system, it should be a byproduct of the game. Chasing credits for specific goals will just encourage credit chasing, in my opinion. The match making play should be about winning being the ultimate goal. Personal achievements in a game like kills, sprees, and the like should be balanced for each game type. Team play, kills and assists weigh heavy, but are of less value than a team win. FFA would be geared different for the obvious reason and so on down the line. Team play should truly encourage team play, especially in the ranked format.