This would be a nice feature. I am trying to get some buttons in pretty specific spots (down to the pixel) and its just extremly hard to get it in the proper spot with the mouse - espically since i am mostly using VNC to configure housebot. A CTRL+Arrow key 1pixel move would be ideal in this situation.
What I usually do is to get them in the general area with the mouse. Then switch to the "Position" tab of the property window. Then I click in the edit field for the position value to change and use the cursor keys to move pixel by pixel.