The liberator is a bastard of a 30's hidroplane, a WH40K Fighta' Bomba and a WWII HE-111...
The secret behind the TR mossie (with rockets) may be in Higby's hint in the PCGamer preview yesterday. It says "Each of our fighter has it's own skill tree that lets you costumize it to be an air fighter, an air to ground fighter, a super fast reconnaisance craft, all from one plane."
So my bet is, that this is the air to ground variant with 16 unguided missiles (and a huge airbrake opebned on the top). It IS a mossie, but costumized to be A2G.