I will look into improving the key bindings or at least give some kind of description how to adjust the shortcuts to your liking.

About the quick access controls, as far as I know only one icon per extension is allowed but correct me if I'm wrong.

Update on this: With Firefox 60 it will be possible for extensions to update their key bindings. I will add this to the extension settings as soon as the release of 60 is coming close (Q2 of 2018).