From a couple of sources have come some official image of wave 2, and listings of future Hero Mashers, which all seem to be of RID characters this year.

Wave 2 (which we sort of saw on display at NY Toyfair, mashed up with each other, so these are official images)...
Optimus Prime
Strongarm
Clampdown (packaging actually says Clampdown... which I mistakenly thought was Bisk at NY Toyfair, because they are both crab/lobster themed & red)

Future waves (no images)
Bisk
Drift
Fracture
Jazz
Quillfire
Thunderhoof