My favorite corruptor is a Beam/Traps. I don't know if I'm an expert in the set, but I've got some good experience.
Biggest thing to remember is that Lancer Shot has a 100% chance to spread disintegration, so my first attack (when not nuking) would be Disintegrate followed by lancer followed by the cone attack. That combo brings some extra damage to BR's otherwise lacking AoE potential.
I personally like the narrow cone attack as a ST attack, it provides -res, though admittedly, it has a bit of a wind up.