Regarding the Zeiss-Hartblei lenses I would say that the 120/4 and the 80/2.8 is using the same lens groups my 120/4 and 80/2.8 have, with some improvements like better control of flare and circular aperture.
The Hartblei 40/40 is based on FLE IF, that is a new construction much better than my 40/4 FLE.
The points you mention on technical cameras is interesting. The best option on technical cameras is calibrated focusing scale and lenses like Rodenstock HR, calculated for a large image circle. Precision focusing ring and a laser distance meter can handle focusing and the lenses are really good.
Regarding focusing on MF DSLR, this image shows three options:
It shows what I can resolve visually, red frame is waist level viewfinder with loupe, blue frame is Hartblei 4X focusing hood, yellow frame is PM5 with the Zeiss 3X monocular I normally use for focusing (9X in total). You can see that the sensor resolves at least four groups more than the best I can do on the focusing screen.
Using a 15X peak loupe is still not good enough to match focusing by actual pixels in live view, what I have seen.
What about the Zeiss-Hartblei lenses, the Canon 24TS and 17TS? With the A7r you got your technical camera. Which technical camera will be better? A MF back with no real live view and lesser DR? With the A-Mount you will have to sacrifice anything wider than 40mm.