Those look like my original style fixtures. I've had the drawings on my site since forever so they could be ones I made or ones someone else made unless you know you got them from me. You've got to love building with them. If you ever want to update them to the current system let me know.
Sometimes I get the urge to do a tissue job just because so no argument from me on that. I do find that glass sands a lot better though than dope though. The idea is not to put too much resin down in the first place and then actually let it get hard. It sands very nicely.
Personally, I wouldn't hesitate to use it on a plane as small as an R/C .020 job. Seriously. So to me the work is easier than tissue, but that's just a matter of personal experience and preference. I use nothing but clear over glass all the time. Check these out:
http://www.airfieldmodels.com/galler...stik/index.htm
http://www.airfieldmodels.com/galler...k_30/index.htm
http://www.airfieldmodels.com/galler...s_01/index.htm
All are glassed. Some are coated with clear epoxy paint and some are coated with clear oil based poly.
All your other statements are certainly true - tissue is definitely more widely available and far less expensive.