Upload & Sell: Off
I went through the same realization (tired eyes ) just about a year ago. It was more a case of - I was missing people shots - than not being able to focus in general - but basically my eyes , along with the rest of my body, are getting old.
So I sold my Canon system - 5DII along with Zeiss 35 f2, 50 1.4 and 100 Macro. It was hard to part with the ZE's - I really liked those lenses believe me! I then bought a slightly used (500 clicks) Sony A900 with Zeiss autofocus 16-35, 24 f2, 135 f1.8 along with some misc. Minolta - Sony glass.
I must say, I have no regrets at all - the A900 VF is fantastic, the build quality of the body is unsurpassed IMO, and the ZA glass is Zeiss all the way. Perhaps a tad off from the build and IQ of the ZE's but - contrast, color , micro contrast, pop and 3 D are all there.
I tried a Sony A65 EVF but really could not see much through the EVF in bright light so I stuck with the A900 view - an A99 does not interest me for that reason .
The VF in the A900 is so good I often use the manual focus on the Zeiss lenses unless things are in motion. However, the real reason to stick with the optical viewfinder (for me) is it gives me an unsurpassed view of the scene which lets me compose the picture - that is critical for my style of photography. (Please no arguments about EVF vs OVF - this is merely my experience.)
Meanwhile, I picked up a Fuji Xpro1 body and 2 Nikon Zeiss ZKv2 lenses with a Metabones adapter - 35 f2 and 50 1.4. I must admit the ZE, ZK lenses are really top end equipment - unsurpassed in IQ and build quality - I had missed them. The Fuji also has a 2 tier magnify which I use to focus - even my eyes have no trouble with that. However, it is a 2 step process that I use: focus wide open, stop down, then fire. Once again, not great for moving objects but certainly do-able.
Keep in mind this is just my experience - but I will say - I am very content with my systems right now. The potential image quality is a at least as good as I am a photographer, and I enjoy using the equipment.