Ulrik, I already have the cv 1.1 nokton as you know. Amazing lens. You should copy my exact kit (albeit with the 35/1.2) 21/4.5 c-biogon, 35/1.2, 50/1.1 & 90apo...
EDIT: oh I see you were keen on the 90 pre-asph, also a great lens, very different to the 90apo, but better close up performance IMO, and the bokeh has less tendency to be edgy if focused up close.
wide open:
Has (much) more purple fringing but f/2.8 & f/4.0 is very similar and indistinguishable from there onward (sharpness and bokeh).
kidtexas, I agree with many that 75 is very close to 50, and also have been very pleased with the 90 apo on SLR. If I didn\'t have the 50/1.1 I probably would just go for the 75 apo and use 21/35/75 only.
21/4.5 c-biogon, 35/1.2, 50/1.1 & 90apo... 