JPNola
Veteran
I have to agree, my old Zeiss Contax lenses make very pretty pictures.
I do like the look, but it isn't a look what would work for many of my jobs such as live shots, sports news, reality tv, feature packages for tv shows, or bts on films. Great for commercials and music videos, but not for clients who want a "live" look that is high contrast, punchy, and with deep blacks. That HD look that is almost 3-D looking.
It is unfair to characterize the Zeiss Contax as a specialty look? Milky, flat, and flarey. I wouldn't want my only primes to be Zeiss Contax. For me they would be a specially prime set that I pickup after building a more modern set of primes.
My advice would be to not overthink this and go with the Rokinons or, if budget allows, Canon EF L primes. The Roki's give you a manual iris ring. The Canons are the higher-end glass that the price suggests. Start with the Canon EF 50mm f/1.2 L and build from there. The Canon EF glass will function quite happily on a C300, Fs7, 5D, or A7s. And EF glass generally holds value should you decide to move up the prime lens ladder.