Are you tanking or DPSing? If you're tanking... pretty much gotta use tab sometimes.

In groups I have 'T' set to target target's target. Meaning whatever the tank is working on, I can target it.

If you're soloing this isn't much help. But you don't have to target the mobs with tab. Everything you are fighting should appear in the lower left. I'm not sure how to use that with a controller, but if you're using a mouse you can click on them and target them that way.