I'd also throw some Corruptors into the mix, if you really want to pew pew and solo through content quickly.
I have a Selene from Underworld dual-pistols/dark, which is just a theme build, but was fun.
You can pair a number of 'techy' secondaries with DPs with a corruptor which will add a lot more versatility to your build than just an armour or melee blapper powers, imo.
Plus, SCOURGE!!! 🙂
FWIW, the most survivable blaster I ever built was a dark/ninjitsu, but that's not the theme you're looking for, eh.