Eric, I agree with all of this, but have one comment about size advantages.
For a long time ... I was an advocate of mirrorless because of the size of the camera and lenses. ... I now ... have come to the realization that the best reasons for mirrorless are the EVF and its options for magnification for manual focus, the lack of a mirror for accuracy of focus and a whole bunch of others.
There is still one respect in which an EVF does help with allowing the _option_ of downsizing, even though there are also good reasons to combine an EVF body with big, bright, fast lenses. This is the fact that the far greater low light handling of modern sensors compared to film means that, when the reason for using those big lenses is speed (rather than the esthetic goal of very blurry backgrounds) then the same speed and low-light handling can now be achieved with far smaller, lighter lenses. The speed achieved with 35mm film and the fastest lenses can be matched or exceeded at about f/8 in 35mm format, but also at about f/5 in APS-C at 2/3 the focal length, f/4 at half the focal length in 4/3", and so on.
But no matter how this lens downsizing is achieved (with or without sensor downsizing) it means that these smaller lenses gather light far less quickly than do the big, bright lenses of the film era and of high-end 35mm format DSLR usage ... and this is a problem for optical viewfinders, at least with manual focusing!
A common complaint in this forum and others is that the OVFs on DSLRs in the new sub-35mm "digital only" formats give an image that undesirably small and/or dim. And if one stays with a good 35mm format SLR viewfinder but downsize the lenses to f/8 or slower, there would be the same OVF dimness problem in many situations. (Try DOF preview with the lens at f/8 to see what I mean.)
I suggest that the coming preferred solution for this "kit downsizing through lens downsizing" is to abandon the OVF in favor of an EVF (or using the rear screen if and when you are comfortable composing that way.) Therefore I do still see the case for EVF cameras being strongest with the new smaller "digital-only" formats, even if there is also a good case for having EVFs as an _option_ with 36x24mm and 44x33mm sensors too.
Entry-level APS-C DSLRs with their small penta-mirror OVFs of less than 100% coverage might not be on the market for many more years.
