In the drawing environment I'd like to see these two improvements (standard in AutoCAD by the way):
1. The ability to type text on a dimension which you can choose to place under the dimension line - In AutoCAD this function could be performed by typing \X after the upper dim text. Just a button or even copy the script for \X would suffice!
2. Decent options for snapping leader lines to help place them better - at the moment all we have is the (sometimes useless) dotted alignment feature when you go near another dim leader. Perhaps we could have a basic dimension constraints toolbar in the ribbon? You only need a couple of buttons, say horizontal and vertical alignment snap?