Apart from soundtracks you sound similar to me. I dabble with classical, play a lot of blues and boogie as well as rock styles and have spent a lot of time playing Jazz (quite badly). I'm a master of none of them! Soundtrack wise though I can't help you.
Have you thought about Ragtime, particularly Scott Joplin? He wrote some wonderful stuff, apart from The Entertainer (The Sting). Some of it isn't that difficult and it can be a lot of fun. Alternatively there is a ton of great Jazz stuff you could get into.
Obviously I don't know whether you have a good ear, or whether you are a good reader or both. But if you are reasonable at one of these then lead sheets for Jazz tunes, and learning to improvise (if you can't already) would be something new.
Years ago I spent a lot of time picking up bits and pieces from a lot of rock/pop players. So if you ever heard me at a gig (unlikely these days) you'd hear bits of Elton John, Reese Wynans and Prof Longhair coming out of my fingers.
To be honest the choices out there are endless. My general rule of thumb is to practice and play what I enjoy listening to. Quite often its what I'm listening to currently. So for example at the moment I've been listening and trying to play a lot of Chick Corea (not easy!).
Hope that is of some help.