Trimmed section speed control

It is really essential to control speed of a trimmed section. For example when I record how I use some application and I have to fill a form or write a long text. It would be really helpful to make the speed of such section x1.5 / x2.0 / x3.0. Or slower. Would be great to have a slider from 0.5 to 5.0 with a step of 0.1.