Well that would be the first actually scary portayal of a decepticon on the big screen since Unicron in 85/86. 😛
Besides Megatron'll probably be a giant radiator in the next movie (for "realism's" sake, of course 🙁 ) and Witwicky could trip out watching the radiator girl (Rumble) singing and dancing, squishing little Scorponoks.
Frenzy's decaptitated head is picked up at Hoover Dam by a small kid who takes it to be made into pencil erasers.
The screen play would open with that shot of the man in the asteroid (played by Bay) who as in the original pulls the lever, and the worm thing (A metaphor for the credibility of the TFs) falls into that puddle of spunk or whatever it was for eternity.
The falling and splashy spunk and psychoticness would then be the perfect opportunity for a sequel:
Transformers / Ichi the Killer. 😛