I'd love to get Schneider's opinion/input. I think they're aware of such issues as evidenced by the 350mm Apo Tele-Xenar, which fills a "hole" in the lightweight 4x5 lens lineup at that focal length.
As you noted, simply producing new Dagors is probably not desirable because they'd be competing against a huge used market and the Goerz brand. And a f:6.8 - f:8 - f:11 SS XL series might not need much in the way of re-engineering or setup, since the basic design would seem to be completed, and glass and shutters could be very much smaller. I can see that as a true replacement for all the features of the Dagor, except probably price - but you can't have everything.
Sign me up.