General Maulvous
Okay, so here we go. This is where conjecture takes over so bear with me. How different would the story be, if General Grievous was actually the resurrected Darth Maul? He would still have a hatred of Obi-Wan Kenobi, hed still be playing against the Jedi, hes still have lighsabers (hes had a double one, so four seems the next step to topping that), hed still be messed up and be housed within his metallic shell and hed still end up being taken down by Obi-Wan except now it would be a genuine rematch, not just one hinted as a previously unseen head to head in the Clone Wars. I know what youre thinking. But General Grievous doesn't have force powers. Thats fair enough, but with the description of Midichlorians in Phantom Menace, Lucas explained how they live within us and work with us to use the force. With a reduced amount or organic matter, arguable Anakin Skywalker is weaker as Darth Vader, Palpatine certain sees him as a reduced version of what was the vast potential un-messed up Anakin was, so arguably, if General Grievous was ever envisioned as a resurrected Darth Maul he wouldn't have force powers, or they were simply taken out when the idea of Maul was shelved. As it is, Grievous depicts a step on from Darth Vader. A much more reduced half man half machine. If this was played as Maul, and he proved as useless as Grievous was, this would later mean that Anakin in the Vader suit was a Sith sitting somewhere between full glory and worthlessness in his post Obi-Wan duel state. It still sort of does but with Grievous, the benchmark is lost as he had no force abilities. So far in the prequels we've had a character to judge Vader against. Maul (Ultimate Sith), Dooku (Fallen Jedi) and with Mecha-Maul we would have seen a force sensitive baddie a step too far beyond useful for Sidious. Next up is a little thing that gives my Maul lovin heart a Sith beat. Its a bit of fuel to add to the conjecture fire but take a look at this animatic from Revenge of the Sith depicting the full chase and fight between Obi-Wan and Grievous. Remember this is simply an animatic and doesn't mean a whole lot but take a look at the eyes used as a reference for the crude character animation for General Grievous. Look familiar? http://www.youtube.com/watch?v=kuJweMUeSVU You can watch this clip in better quality on your Star Wars Blu-ray boxsets but you get the idea. Of course this is by no means evidence Maul was ever planned to return in Episode III. There are a number of reasons why Darth Mauls eyes would be used in an animatic but for me, seeing this animatic on the Star Wars Saga Blu-ray collection when it was released reminded me of my little fanboy thoughts on where this General Grievous character idea might have birthed from. Also it a great job at highlighting how this would all still work if that was Maul beneath a robotic outer layer. Also it's interesting that in this early take on the scene Grievous ends up dropping down a chasm much like what happened to Maul. If this was a rematch, that would have a certain echo to it, right?