I would hire Quentin Tarantino to write/direct(with assistance from Garth Ennis) an adaptation of Ennis' comic book "Hitman".
Hitman is about, well, a contract killer named Tommy Monaghan. He lives in an Irish-American ghetto in Gotham City. Tommy runs into Batman and other superheroes/villains from time to time, but he mostly has to deal with all the other lowlives from around the area. He was attacked by an alien parasite during a hit, and now has the powers of telepathy and x-ray vision, but he only uses them to enhance his prowess at killing people. It's an awesome comic with great dialogue and humor, and Tarantino would be the guy to best represent it on the big screen.
Tommy Monaghan would be tentatively played by Colin Farrell.