Haha, I could never get used to using the number buttons on my keyboard, I am faster with the mouse anyway. I use 1-3 for my directional combat, everything else is my mouse.
This works well for me too, although I sometimes lose focus of pointer and struggle to hit the buttons once in a while, I'm going to have to look at remapping maybe q and e and c and other keys around wasd for combos, although the reliance on the 123 keys for fighting makes fighting and moving trick to begin with.
Theres probably a better way to do it with mouse buttons isntead of 123 keys, may tinker with that today.