Tom I have two 35mm lenses that I use with my A7R and A7S, neither of them the Sony FE.
One is the Contax Zeiss 35mm f/1.4. It has a beautiful look on both cameras, and a fall off that is legendary. It is sharp wide open, with great micro contrast. It does have a bit of C/A on strong backlit subjects like fine tree limbs, as most of the older film lenses have, but that is easily corrected in post.
Contax Zeiss 35mm f/1.4 with adapter on Sony A7S
It is not the smallest lens in my bag though it is interchangeable and works fine on almost any camera made, including my A series Sony bodies, Fuji X-E1, Panasonic GH3 and a Canon 5D Mark III. I am waiting to see what the new Sony Zeiss 35mm f/1.4 is like, but it is going to take more than just autofocus to get me out of this lens. The new autofocus lens I may add, but the drawing signature alone is a strong selling point for the whole Contax Zeiss lineup. This lens is a classic for a reason, a great lens for both still and video use.
Contax Zeiss 35mm f/1.4 wide open on Canon 5D Mark III.
Contax Zeiss 35mm f/1.4 @ f/5.6 on Sony A7S
My second choice for the 35mm focal length is a version III Pre-ASPH Leica Summicron. The 'Cron is magical on both of my Sony bodies. It has excellent resolution edge to edge across the frame, remarkable micro contrast, and near perfect color. As you know, the 35mm 'Cron weighs almost nothing and it is TINY! Lens cap and all it comfortably fits in a front pants pocket, but it practically lives on my A7R. I absolutely love it with both stills and video. Every lens should come with a focusing tab like this 'Cron has. I have zero problem nailing focus using focus peaking with the A series bodies. The later ASPH versions of the 'Cron have a different look. This one has the Leica "glow" and wonderful soft background wide open, but still with plenty of "juice" stopped down. A classic high quality optic because it is such a unique drawing signature in such a small, compact and light package.