I assumed that the blue glow was from some sort of ionized gas, but I also assumed it was there on purpose. I suspect it is one of the inert gasses, but I dunno. Sure is nice though.The Sophia tube sounds interesting. It also sounds like it is neither 300B or 2A3, but rather a third that shares some characteristics of them both. Sort of in between as far as bias and load line goes. Interesting.
You've really got your hands full there. All those projects, grandkids and a Masters to defend. So I'll understand if you nod off from time to time.