everyone has different results... ultimately you'll most likely rank up fastest in whatever type you are best at... try this, go to the leaderboard and see what you point per minute total is for each gametype... in theory, which ever one is highest is the one that you personally will rank up fastest in...
TDM is better than a lot of people think... you may only get like 2000 points per match, but sometimes the match may only last like 4 mins. headquarters nets you a lot of points, but many times lasts the full 15 minutes... i like HQ, but it kills you K
due to random spawns...
I personally just try to get with a group of buddies and have fun, ranking up isn't even important if i'm having a blast playing and shooting the breeze with some friends, and before you know it, you've prestiged a few times