I'm no expert either, but found for the motor forward position *not* triming the rear wing down also helps as the KF is quite a nose heavy car I believe. Idea being, more drag at the rear levels it out.
Easiest way to make the steering less darty is to run the shocks on the rear (need the alloy g/b housing to achieve this).
I didn't like the shocks on the rear though, made my KF feel too lazy, so I made some extended wing mounts to just move the wing back by around 1cm to calm it down a little, but not too much
5 dgree hubs as per the above is a great tip also. Don't know anyone that runs the originals..