nikon 35mm or 50mm

Recently bought D750 and a 16-35 f4 VR lens.
I'd like some thoughts on whether to get a 35mm or 50mm 1.4 or 1.8 prime. I do no commercial work, but some freebies for friends, and enjoy inside and outside work. I want good quality, price not a problem, but I'd feel foolish to spend more than I need. Comes done to 35mm or 50mm?

Thanks for any experienced advice.

Since you already have the 35mm covered, I would go for the 50 and see how you get with the focal length. Some 'feel' the 35, others the 50, I'm a 50 kind of guy.

I feel that the Nikon 35's from my reading are a bit better than their 50's. The 58 is pretty darn good too, just not 4-5 times the price better than the 50/1.4G or 10x better than the 1.8G IMO. The new 35/1.8G is a great lens from reviews I've read, almost matching its bigger brother.

IMO though, none of those quite match the Sigma 35 and 50 Arts. I have no focusing problems with my Arts on my D4 and the D750 is supposed to have an AF system that is at least as good as that on the D4.

For relatively inexpensive experiments though, try the 50/1.8G (as DavidR mentions, it will add a difference to your 16-35) and if you feel that's too long, try the 35/1.8G (I'd start with used so that you won't lose so much on resale). Or just get both. You could get both of the 1.8G's for less than the cost of the 35/1.4G and not much more than the 50/1.4G. Together the two 1.8G's would probably weight around the same as one of the two Arts I mentioned. The 50/1.4G isn't significantly better than the 1.8 either other than offering 1.4 vs 1.8 in wide open aperture.

Hmm, well if you will, tell me a bit about the sigma 35, and why you like it. Would it do 'better' than a Nikon?

IMO, it is the sharpest AF 35mm on the market. It was always the lens I had on the front of my old A7r for general walkaround duties. I like the heft, the focus ring feel and the IQ.

It's also around half the price of the 1.4G.

would it be better than the Nikon? I think so: for my desires. I have seen some call it a slightly more "technical" rendering than some of the other 35's and since I generally don't shoot portraits, it's not an issue for me.