I´m still learning, so I appreciate a lot your feedback!! (Don´t know what residual jittering is, but I will search for it).
I used this keys because for me it´s better together than separate, but I see your point... Hehe. The dash control for me, that I played the levels maybe 100 times, it´s ok. For me it was difficult to find and code a combo that could not be confused with the usual jumps.