Hi b0wfin,
Nice looking Pilot! And nice jobs with the upgrades! I just got here, but I'll be following your build from here on out...
You and I have taken an almost identical path: First gen Pilot, 2" lift, air springs, etc. I too started with separate air spring valves but, as you did, eventually went to a single-path implementation. I find it interesting that you have trouble with your air springs holding air--I have the same problem. I think I have an honest-to-goodness leak, but the fact that your bags leak down may indicate it's just the nature of air springs. I've gotten so sick of finding my bags low half-way through a trip I installed the AirLift on-board compressor. Crazy expensive, but it works great.
I heard in one of your videos that you're thinking of running 235/85R16 tires. That's what I'm running and, be advised, pending on brand, they rub under compression. When it comes to flex, 245/75s may be the sweet spot.
Question for you as regards Hi-Lift jack usage: Have you found any good lift points on your Pilot for your Hi-Lift?! As you probably well know, with the 2" lift and larger tires, the OEM jack is no good. And while I haven't done an exhaustive investigation, I can't find a good lift point to use with my Hi-Lift. How are you doing it?
Best of luck with your build!