One thing that will add a little fun to our basic rail slides & box slides, without increasing the risk too much would be trying things like urban-ons and lipslides.
Urban-on basically means that, instead of coming at a feature straight on, come at it from the side and lift your noses over the rail; while lipsliding is the opposite, with your tails coming over the feature. They're really not any more difficult, if anything they're easier on a lot of features (in my opinion).
Urban-on is fairly self-explanatory, but here's a lipslide video:
Other than that, try working on 270 outs, and sliding with your bad foot forward.