The thing I appreciate about an EVF vs an optical VF is that when I am looking at the scene, about to compose and frame an image, I also can quickly check out the exposure values and see what happens if I make adjustments -- so, the scene looks fine as I'm initially studying it through the EVF, but what happens if I adjust the exposure values up or down? Change my f/stop? Tinker with the IOS settings?
Sometimes for creative effect I like to really take advantage of spot metering and it is nice to see in the EVF when the scene will look the way I was envisioning..... At other times the EVF can be very useful, too, when I've got the camera focused on a scene and yet something doesn't look right about the lighting, the exposure.....I can immediately see this and make the appropriate adjustments before ever clicking the shutter button. No need to see the error after the fact by "chimping." I see it immediately and can fix it and then get back to my subject, my image. I often have my ISO set at Auto ISO, but occasionally something will happen and it slips off that setting and all of a sudden things don't look right at all, and because I can see that through the EVF I know to take a look at my settings, especially the ISO, to see if something has shifted from where I had intended for it to be.
The first few times some years ago when I first encountered an EVF I thought it was downright weird and it took time to understand the potential value of it to me as a photographer..... Now I know I would have difficulty in going back to a strictly Optical VF.