It's always cool to see an accomplished voice actor take such pride in what would seem to be a footnote in a long career...maybe there's some greater significance to this "Transformers" thing after all...
Still, if the original buzz about Megs going "boom" at the end of the movie is to be believed, and the producers' current statements that the second movie is still in the brainstorming stage...maybe there's a chance this wouldn't be the last we've seen of Megs, and as such, maybe he would return in a new form differing enough from the "cyberspook" body that he would have an altogether different voice...
Hey, it worked for Galvatron. And though changing the name might be one step too much, it'd be cool if the change in Megatron would be enough of an open door to dismiss Weaving (who, if there is no publicity for his role, is either a "surprise" or he's not coming back for future involvement in the project) and give Mr. Welker a chance to reprise his old role. Not to besmirch Weaving's quality of performance--he could deliver his lines flawlessly--but it seems as though the
concept of having the old Cullen-Welker "rivalry," along with having two veterans of this particular kind of acting, still wins out for a film series "in tribute" to the Transformers.