1)Maul was as the coolest thing about all three prequels, and can hang with anyone in the OG movies. And I'll fight any man who says different.:icon_evil
2)Technically, Maul wasn't an Apprentice, as Sideous began training him while still apprenticed himself to Darth Plaguies. He was trained as Sith Assassin, which is the Sith equivalent of a Black Ops operator. He was supposed to be used for high risk, surgical strikes. Most importantly, he was expendable, which is why Plaguies allowed Palpatine to train him in the first place. Sideous referred to him as an Apprentice simply as a matter of form, and to boost Maul's ego.
3)Phantom Menace wasn't Maul's first rodeo. It wasn't even the first time he fought and killed Jedi Knights. Maul has been used on several black ops long before he arrived on Naboo. Including a highly successful mission against the Black Sun, the Star Wars version of the Mafia.