Pan zoom feature request

I use pan and zoom a lot on photos. You have a start frame and and an end frame and you can toggle between them. What would make life so much easier is if you could also get a reverse toggle, so that what was the end frame becomes the start frame and vice versa. This way you could (after duplicating your first setup) make progressions from, say, a pan to a zoom sequence without manually trying to match framing on that tiny impossible mobile interface. (I work from an Android phone on the latest version of Rush)

On that note, the ability to work on a larger scale would help greatly. My big fingers can only pinch so much on Rush's microscopic preview UI.