So I bit the bullet and rolled back my work on the bomber, starting again from a VGC Turquoise base. I failed to take a picture of that, stage, but working from my previous ending point, basing it with Turquoise, and moving foward, the images below show where I currently am.
Still, after a good soaking in cleaner, my airbrush will make short work of the white high points, and I think I'll approach the pigments only after spraying a coat of varnish so that I can just wash off any crappiness that results from bad or uneven pigmentation application. I went back to, on this attempt, using a mix of water AND alcohol to thin the paint for airbrush application, and tried setting my air pressure very low and using "full" air application (finger all the way down on air trigger). Before the airbrush became unusable, I was VERY pleased by this technique's very thin application layers and I'll be using it on all subsequent models.