For me it is not the fact that it is a EVF vs a OVF. (A7RII)
Its the lag in coming on when you put the camera on, or wake it.
Its the lag in taking the picture, and preview.
focusing in the dark even in magnify mode the EVF looks blotchy
Its also a setting that I think should be addressed in firmware....
When using the camera, mainly due to battery, and not being distrancting and having your monitor on the camera lit up all the time, I turn the EVF/Monitor Auto mode OFF. SO Only the EVF comes on when I put my face to the screen, IF I am manual in EVF mode, otherwise the Monitor is off, and I have a shortcut to turn it on....
BUT, When you use EVF to shoot, to get to a preview, and back to shooting is a 3 button round trip!
There needs to be a mode to take the picture in EVF and auto preview in the monitor regardless of where your face is. Its nice to pull your face away and look in front of you the scene, and know you have the preview for a few seconds.
I actually like seeing the peaking. I also now found a setting that will brighten the screen to focus and not mimic a dark scene if I am in one. So the advantages are many for me. I think the problem is the rest of the system needing to catch on. Maybe it needs a Bions X100 multiplier?