It has been asked for many times by many users including myself. CK has always said that it won’t happen because a really leslie has fixed speeds and the effect is designed to replicate a real leasie. However, he also said there would never be an Android editor so who knows 😆
It's been a few years since I made the request and hoping that this might Stoke some interest. And a real Leslie does have these features. As a keyboard player I am surprised that CK does not reconsider this especially as a keyboard player.