Firstly you all seem to ignore that Darth Maul was also a throwaway Villain. A pawn. He failed in his mission and yet Sidious [In the guise of Palpatine] came out on top and acheived his main goals. The same goes for both GG and Dooku but People seem to like Maul a whole lot more, Probably cuz he kept his mouth shut most of the time...
WHY would Sidious bother putting the effort into rebuilding Maul? What he now needed was
1 - A charismatic leader for the CIS [dooku]
2 - A Military Leader for the CIS [GG]
3 - Someone who could bring down the Jedi order from the inside [Anakin]
Darth Maul could fill none of these roles.
Secondly the two characters have nothing in common as far as I can tell. GG bears no similarity to Maul at all...
- He's always talking
- He relies on other to get the job done
- HE IS A COWARD
- His lightsaber tactics leave a lot to be desired.
Do you see any of those traits in Maul?
Plus i don't think it can be done convincingly - his eyes aren't even the same shape or size.