to me it depends on the map and what job your doing, if your going for kills then go for dictator with thunder, that will kill almost anything and you can take a hit or 2, and if you upgrade it, that just makes it all the better. but if your going for defense, like defending the flag, get the titan with your choice of railgun, or thunder, as they both do high damage, or if you really want you can use smoky if your going cheap, as you can soak up damage and you want to kill them before they get that flag as that build isn't ment for speed, just taking hits and dishing them out. and if your going for caps, get the wasp and get either the fire bird, or freeze, or if you have the money and rank go for the ilias (something like that) as if you attack your going to hit from close up, but your not going to be attacking your mostly going to want to rush and just grab the flag and get out, the more time your in there base, the longer the enemy has to kill you as 9/10 your teammates are not going to come and help you, your going to be independent so you want to just run grab and run some more, also even though its easier for them to shoot, go straight as going curved only slows you down and there going to hit you no matter what, sadly its the truth