Let me add my compliments on a very interesting and tidy looking project.
I'm not competent to review 7JP4 designs, but if you are curious about comparisons, you might want to include the National TV-7. The build quality is certainly nice and I believe it has DC restoration, something not always seen. The schematic is available at ETF:
http://www.earlytelevision.org/tv_sc..._diagrams.html
Regards,
Phil Nelson