I agree with your alignment tech. I've experimented with all kinds of caster angles up to 10 degrees on the road course. I don't like the feel of the inside of the car lifting when using a high caster value. It produces a very unsettling feeling going into a turn. I run approx. 4 degrees.

Secondly, I sell and have the Borgeson steering boxes because the feel is way more precise than the factory box.

Just my .02.