I am a keyboard player, and have a couple of suggestions that could greatly improve the combat experience.

1) Give us the option to turn off the Action Bar cursor, so that while trying to target the monster attacking us we are instead scrolling frantically through the Action Bar. Maybe with a text command of /actioncursor on|off

2) Enter Auto-Attack by pressing the Enter Key only once. Make Auto-Attack the default action when an enemy is targetted. This will also make it easier to retarget enemies who have target breaking abilities.