Without repeating what has been expressed in the many excellent posts (and discussion here) and most certainly all you expressed, I would ahve to admit that your feelings about focus confirmation and how I too think it should be implemented, are near identical...as is out expectations that a rangefinder like the Leica M is mostly for spontanious hand held shooting. I so far am not a fan of accessories in the shoe on top of the camera and rarely of Live view on an LCD unless maybe I'm deliberately on a tripod with a DSLR.
A simple red (or for Guy a "green") dot in the viewfinder to indicate maxium phase contrast of the part of the subject that one is focusing on, would be welcomed. Whetehr some sort of magnification fo the optical viewfinder needs to be implemented to achieve this, might be necessary. For me personally, a M rangefinder shoudl be versitile but not turned into a psedo DSLR. I respect though that everyones needs and desires are different.