Yoshi's Island had a massic boss battle years before Armada. :P But that's just nitpicking.
While a G1 game would be well-received by the fanbase (assuming it doesn't suck), I doubt that would be enough people buying it to justify not basing it off the more prominent movie franchise.
I for one liked the movie game, although the one I played was the DS version, which was awesome in a small cartridge. Unfortunately I lost it, but there are loads of old stock around going really cheap, and a new game will be out soon, so I'll buy the new game since I don't particularly want to play through the same levels again.