Imagine Darth Maul and Sidious vs. Darth Vader and Luke or Count Dooku and Starkiller, interesting Fight/Battle. Also Imagine if Maul hadn't been killed in Episode 1, would Sidious have him do what Dooku was doing with the Clone Wars, Separatist, and train General Grevious or would a Angered Dooku haunt him down for the murder of Qui Gon?
Maul's life sucks. I cannot help feeling a bit sorry for him. But, he is an asshole and mistreats people horribly, when he could have done differently.
I know sheis only mention a bit, but my heart breaks for Ahsoka. She is a child soldier, and one of the people she8 deeply trusts turns out to become one of the worst villains.