When we in Japan last March Mr Kobayashi and I discussed the idea of a 35f1.4 extensivly. The parameter were simple, an improved version of the latest 35f1,4 pre-asph with less agressive texture of the 35f1,4 asph and less prone to flare compared to that lens.
The old 35f1.4 Pre-Asph is a very old design, dating to the early 60's and though heavily massaged over the decades, its age shows. It is still a very good lens, but things like field curvature, coma is prevalent, particularly in the "fast" apertures.
The CV lens will have adressed that. Modern computer design and upgraded glass will make a difference.
For those who are using the 40f1.4 Classic Nokton (Multi coated) you will probably recognize the "draw" of the lens, but i suspect that the new lens will have improved over even that lens!. Mr Kobayashi likes making lenses and he takes pride in improving what he makes as he goes along. The CV designers are extremely competent and when it comes to fast optics, they probably have more experience in it than virtually anyone else. CV is one of the foremost producers of ultra high speed optics for surveillance cameras world wide!
I have not yet shot with the new 35mm f1.4 but in the meantime I am sticking my pre Asph 35mm f1,4 Summilux on a M2 just to gather up some stuff to compare with the new one when it arrives.