Good points. Somewhat known, perhaps overlooked - I had a mirror-less system back in 1976, it stomped on all the Canon, Nikon, Leica and even Hassy offerings... It was the Deardorf 8x10 with a set of 3 Schneiders of various focal lengths. Had dynamic range that was unparalleled, could crop the image like crazy - you get the point. (Frames per minute or even minutes per frame might be another parameter ) (yea it wasn't mine, it was the camera stores'/studio in which I worked but I got to use it on Sundays).

Bigger sensors have behave/need differently than smaller sensors. What was grabbed as an advantage was a marketing wiz flop vs. what I think may be the real advantages. With more real estate there are more options. Even in the view camera I could change ISO between frames, even after the film was loaded by changing the development times. Much of this is about compromises in sensor size/density and certainly speed.

Regardless of sensor size (and resulting system size) here is my beef w/ the mirror -

Lots of mechanics that can go wrong.
Sound
Can't electronically amplify the image in dark settings
Can't electronically aid me in focus peaking/highlight/blacks (I have take a frame and look at the LCD on the back - why take the camera away from my eye?

The original advantage of the optical view finder is seeing what the lens sees. Soon w/ improved display tech, we can improve what our eyes see at the extremes of the imaging effort/frame, etc. I for see being able to tone map an HDR view in the electronic view finders some day in the future.

Give up on mirrorless = smaller, rather focus on the electronic aids to the imaging process. I really don't want to bust out my canvas and paint, nor the view camera, nor my old film bodies, nor film. Help me take the best compromised picture for the system size I have chosen.

My 2 pennies.

Mike