I really wish people would stop confidently saying wrong things on these boards, tankers blow brutes out of the water even when soloing.
To answer the OP: I'll just throw all the best options off the top of my head and you can pick what vibes with you best.
Blasters: AR/ta, Fire/fire, Water/atomic
Scrappers: Claw/bio, Energy/rad, Ice/fire, DB/energy
Corruptors: Can't go wrong with ice, water and dark paired with dark, cold and storm. Storm is also really good if you play around it's strengths. Psi/kin is also probably the new best kin pairing.
Defender: Poison paired with fire or procced DP.
Controllers: Illusion+cold, dark or rad. Plant/storm, gravity/storm.
Dominators: Plant/psi, Dark/earth, Mind/dark.
Tankers: Anything with SR, shield and bio will be effectively unkillable in most content. Martial is probably the strongest output set right now overall, a bio/martial is disgusting, but dark melee will be extra good on shield and SR.
Brute: Same as tanker, but they are inferior to tanks in essentially every way. Regen becomes an option, just because tanks don't have it.