First, I just added a very basic fadeout functionality to disappearing entries from the log of shortcuts; it improved a bit the look and feel.
Then I started thinking seriously on how to add a mouse indicator; it took me quite some hours and a bit of wrestling with OpenGL, but I finally got to add a nice mouse indicator!
There are some rough edges, but that must wait for later (or maybe just for another person to work on it).
Enough talking, let's just download it (remove the .txt extension before copying it to the addons folder).
Update: there's also a fresh build with the add-on included.