You might be able to do TurnLeft/Right LookUp/Down and co making it act like a controller, I think all of them can have partial input because when I've played UT with controllers in the past, you can turn half speed and so on.
I don't think it will help you though, when I've played against you/watched you it's like you play in slow motion, I was surprised when you said you have a high refresh rate monitor, you stand still and walk in a straight line a lot, and that's coming someone that doesn't have the best movement either.