Great setup, One thing you didnt mention is the duty cycle rating of the compressor. You did mention the possible adding of a second tank. In my experiments with these systems, I found out the hard way, duty cycle rating directly effects how long you pump will live for you. Two storage tanks are nice, but it will require a longer run time to air the two up compared to the one it came with. If you are planning heavy use, like the air gun for on or off road work, I'd strongly recommend you use a compressor with a 100% duty cycle. I have a system like yours on my PU for maintaining ride height with changing loads. I've already burned out the air compressor on mine. Havent had time to replace it yet, but it will be a 100% duty cycle compressor, with an additional tank this time.
Dan & Loretta, US Army Retired Aero Scout Pilot
2012 Fleetwood Providence 42P Class A/DP
Spartan Chassis, 8.9L Cummins 450HP