Don't know how you got the idea that sith inquisitor class in based on Darth Maul, as the post above me says, just because the class carries a double-bladed lightsaber, dosent mean that the whole class is based on Maul lol.
"Sith Inquisitors were a class of powerful Force-wielders within the Sith Empire, operating primarily within the upper echelons and political circles. In contrast to their counterparts, the Sith Warriors, Inquisitors specialized in Force abilities as opposed to martial might, and many would devote much time to researching new skills to survive in the cutthroat Sith political environment. Few acolytes succeeded in becoming Inquisitors. However, those that did proved to be the most determined."