I had the issue that the OVF gave me eye strain, due to difficulties with manual focus. Particularly in poor light the issues were exacerbated. So, for me the EVF solved all of this with focus peaking and a viewfinder magnifier. Eventually this lead me to sadly leave Nikon, as it was practically an AF only system for me.
As is obvious to everyone, I have no eye strain issue with the EVF, but instead with the OVF.
The Sony A7 came to the rescue, and I have not looked back. Not even today 3.5 years after Sony announced the A7, has Nikon introduced a mirrorless FX camera that would have let me used my Nikkors (since sold) with full functionality.
I had a detour to micro 43, nice weight saving, but full frame beats everything, so no big weight saving anymore, but for me a fully useable viewfinder.
Yes, I know some look down on Sony, but for me returned the fun to photography, and the lenses are just as good as the Nikkors I once had.