I think bike usage is probably largely limited by the helmet designs. At least with Kuuga you could fit little 'windows' of smoked transparent plastic (a bit like the tearmarks of old riders) in the bits where his crest, eyes and mouthplate met on the stunt/action helmet. The guy doing those bike stunts could at least see a tiny bit of what he was doing then. With the later Riders the suit actors are nearly blind when in those helmets, even when not using the more detailed ones for close-ups. So oddly they don't let the guy with his eyes covered over do too much driving about, and when they do it's usually in a straight line.
Part of me hopes that the reason these reflective, metallic visors have become such a big trend in sentai (and now on Wizard) is that they figured out how to put a one-way mirror in the helmets, and the actors can actually see much better. Pure speculation, but if they could do that then the poor schmuk inside could actually see what he was doing and you'd be able to try different things like doing more with the bikes.