Let me say the answer to your Q is: 'it depends'. Depends on what you shoot and depends on what you like/value. So without knowing more about your preferences it is difficult to say what is
best. I would however assume given you're asking this question then you're new to RF and perhaps have not developed a preference/taste yet. This being the case, I will share my personal journey having started using RF not too long ago.
I initially got the CV 35/1.2 thinking i needed the speed. Though it was lovely, as Jon and others have commented, as my first/only 35, it was not to be. Too big/heavy for everyday. Also if i needed the extra speed did not make that much of a difference. Some will disagree I'm sure.
I then got CV 35/1.4 which after using the 1.2 I was in love with the size and weight. Fully open, the pix often came back 'fuzzy' and the bokeh can be 'strange' looking. At 2.8, it's sharp and fantastic. I now use it from 2.8 up and it has plenty of character but I tend to use it with my film M - it just 'works'.
I now have the Leica cron IV. This is most 'sharp enough' for me @ f2 and is tiny. It works well on the m8 and the colour is most rich and pleasing for me. So, this is my 35 on the m8.
My conclusion? I value size/weight most. I shoot wide open often but iso640 @ f2 and 1/15 is fine for most of my needs. I'm don't worry about bokeh and I don't shoot landscapes nor architectures. I shoot mostly colour on the m8.
If you've not developed your taste/preference, then you may just have to 'try and see'.
Some pix...more on Flickr - all appropriately tagged with the lens used.
Leica Summicron IV + m8
CV 1.2 + M7
CV 1.4 + m8
CV 1.4 + M7