Titans just require a certain finesse. I rarely run below a 1.5 k/d as either defender or striker. If you're getting stomped as a titan, either rework your strategy a bit, or try one of the others to see if it's more suited to your play style. With either subclass, I use a hand cannon, sniper, and spec as much close range as possible to have a general attack plan for any situation. There's a lot of options, you just have to try em all until you find one you jive with.