Well first off....just because you play a hunter that does not mean you are good....or that your can bring your class to its full potential. Notice I talk about potential here.....the ability to bring out warlocks max potential takes significantly less skill (talking PVE) than it takes to bring out a titans potential and then hunters potential takes the most gungame skill to bring out its max potential because there are not any abilities you can lean on heavily like there are for warlocks and titans. If you can bring out the max potential of all classes you probably wont see a huge difference in number of kills no matter what class you play as at that time instead you just have to change your playstyle to match the strengths and weaknesses of the specific class you are playing.