Very impressive list!
Buildings are a very interesting thing. I had no idea when I started how many companies were making them - and making good ones, too.
Since my layout is small (9X6) I decided to go for a common theme with tin litho buildings from the long-defunct Skyline Manufacturing Company (I had a good start as my father bequeathed four on me) I now have nine buildings on my layout - eight Skyline tin litho and one Marx Freight Depot, which was just too cool to pass up (Skyline only made five varieties of metal buildings, so there's only so much you can do with them). The one exception is a Plasticville watchman's shanty that I'd had since age ten or so; I simply could not leave that off the layout. So, I painted it with gloss paint for a tinplate-y look.
When I build my next layout, I want to rebuild the Skyline town but also create separate city with the more realistic O-gauge buildings currently available on the market.
Whichever way you go, you really can't lose. Except that it's almost impossible to find tinplate business buildings - Marx made a couple, but that's all I can think of. Otherwise you're stuck with cookie tin stuff.