The Pump-Bump. A great and fun way to 'get speed' is by rolling over the pump-bump. These work really well when placed on a spine ramp, and also work well between to opposing ramps. If there's an area in the middle of your course somewhere that demands more speed, then this is the ramp that will solve your 'slow' problem.
Picnic Table. You might not think of a picnic table as a regular item at a skatepark, but our picnic tables have grindable edges and are built to take the abuse of skaters trying to propel themselves over them. You'd be suprised that skaters find the picnic table a 'cool' item.
Jersey Barrier (above)
Pole Jam (right)