I have thought of de-quigly'ing the van but I think I can actually do a lot with the Quigley system. It just needs a bit of tweaking. The parts are all there, it's just poorly set up and executed.
I'm thinking of building some adjustable control arms with Johnny joints (to be able to push the axle a hair forward and adjust caster). Also would like to try and turn the knuckles to set the caster better.
I'd also like to tweak the turning radius... It isn't hitting the stops on the axle at either end so I think a longer pitman arm would help there. Then I'd have to adjust the stops after that. The tires are nowhere near touching the control arms yet so I think I can get a lot more travel out of the steering system if I spend some time on it.
If I go with the RIP kit from agile, the progressive front coils and shocks should help the travel... Then I just need new leafs for the rear.
It may sound like a lot, but it's not really that bad. I like doing this sort of stuff. I'd rather tinker and tweak than spend money to get someone else to do it.