An idea came to mind earlier: have you considered "regraining" ? Aside from giving it more of an authentic classic aesthetic, it'd sort of alleviate a big issue with the 2004 Lowry masters which is the grain freezing they suffer from. Grain will stop moving and start moving in the background and it's sort of jarring.

GrainFactory3 for Avisynth seems to produce realistic looking grain unlike most artificial grain filters. Also, you could layer on some heavier fake grain to sections that use the GOUT to detract from the lowres murkiness I suppose, could give it a "once lost footage but recovered from worn elements" look to it. Maybe.

But, this really isn't a suggestion, just more of an idea because I know it will affect compression efficiency in a negative way and doesn't add detail or anything. It's basically just adding noise to the video that looks like grain. But I thought I'd throw the idea out there.