bzyguy-
Many of your issues with glow seem to be related to the diversity of powerplants you choose to use. However your use of gas does not seem to be as diverse. You seem to simplify matters by using only a limited size of models that all burn a single octane of fuel with a single blend of oil. I like simple too!
I pursue a similar path towards simplicity with my glow engines. 1/2A engines aside, I run only a single brand of engine, all of a similar size, all 2 stroke, using a single brand and style of glow plug, and a single blend of fuel. I use a glow ignitor that only requires charging twice a year or so and I only mix 1 quart of fuel at a time to keep it fresh. My glow plugs last for a year or more each and I never use after run oil as I run 100% castor oil and have never had issues with rust inside my engines. If my engines get a little stiff hanging on the wall I just heat them up a bit with my heat gun, squirt a bit of fuel or ATF in the intake and flip over a few times. Easy peasy!
For me gas engines have no attraction whatsoever. They stink whether they are running or not, they are expensive and require other more expensive things like more expensive airframes, expensive more powerful servos, larger props, and larger vehicles and trailers to haul them around. For me, saving a few dollars on gasoline based model fuel versus glow fuel would end up costing me thousands.
Although I live in a humid environment I can't recall ever having problems with fuel like you describe. I'm surprised that you had problems with water in your fuel given your much drier climate.
I'm happy that gas has allowed you to simplify things and increased your enjoyment of the hobby. Glow CAN be even simpler if you choose to make it so.