I like the idea of merging position and move tabs: that should not be too difficult.
Likewise, scale and size tabs could be merged by typing * 1.5 in the size field to scale by 150% etc.
Making the interface fully customisable is a non-trivial task, and there is only one programmer — not a whole team. There is sure to be a trade off between improving the interface and adding new features. I think adding real new features is more important than resizable toolbars or ribbons.
Adding a few shortcuts is not a time-consuming operation I think, but I don’t understand which ones are “clearly missing.”
You can add nodes with the A shortcut. You can add new contours with Control C, Control V, or just Control drag.
You can already use a background image to trace around, or just paste one from the clipboard and have FontCreator trace it for you. Is this what you mean?