The only real benefit I can think of about removing the quad shocks is that it allows you to run a wider tire. But honestly, with aftermarket UCAs and LCAs, they serve no purpose. For just that reason, I'd remove 'em.
As far as adjusting the pinion angle (I'm totally a novice, so I'm sure I'll get corrected on this one) - this would require doing some launches (60' worth) and observing the behavior of the car - whether the car wanted go straight down the track or push off to one side or the other. Adjust accordingly to change the car's behavior and get it to go straight, but just a little at a time, and the key here is consistancy. There's my 2 cents about pinion angle adjustment.