Quite often I wish there was a Scale2D available via Gumball (unless I am missing something this is not currently possible, right?). In that case from UI standpoint, how about adding a 4th scale-like handle at the corner of the transform plane? (see below)
Another request or idea: ability to make multiple copies when transforming with Gumball or dragging. Now when we tap Alt, a copy can be made but not until the transform or drag is complete. What would be handy is to be able to make copies “as we go”, transforming the object(s), with a tap of a key. Considering the current key assignments that are “taken” already, how about Backspace?
So basically the Backspace key press would make a copy of the selected objects on the spot, while not exiting the drag or Gumball-transform mode.
Throwing it out there, hope it makes sense and can be considered : )