I’d love to see a toggle between moving by explicit distance (as is the current method) and moving by a percentage.
The percentage would relate to the distance between the control points either side of the selected points to move. There would also be a toggle between U and V.
So, in the pic below where three points are selected, they’d all move different absolute distances but as measured back to the lengths 1,2 and 3 they’d all have moved by the same % of length.
If that makes sense…?