Since Goldeneye Source has been such a huge hit, why not make a TimeSplitters Source?
Most of the Goldeneye team worked on it, it uses a very similar control interface (health and armour bars are identical) and it is possibly one of the greatest games ever made.
According to Wikipedia: "The TimeSplitters series is often compared to GoldenEye because of its many throwbacks to that game and similar developers. For example, both TimeSplitters 2 and GoldenEye start off on a Siberian dam. However, some say that the game plays and feels too much like GoldenEye." but it is still "the best split-screen multiplayer-focused first-person shooter ever created" according to IGN.