Very interesting! And such beautiful images. They make me want to get out my camping gear and hike to the nearest mountain with beautiful views. But first I would have to save up for a 645z...
You speak of the advantages of increased resolution when using the 645z. Lenses that can match the sensor seem to be in short supply. Hopefully that will change in the future, as generally sensors are increasing and so lens technology will be forced to keep pace. Imagine super resolution on a 645z. And you like mirror lenses. Well, yes, they have some advantages, primarily low cost, low weight, small size, and complete lack of CA. What about an autofocus mirror lens like Minolta used to make... it would be a great drawcard for Pentaxians... we like to be a bit different! The technology already exists. I am sure almost everyone on this forum would like a 645z if they could afford one.
Interestingly, you post got me thinking about other ways the 645z high resolution and high IQ could be utilized. In terms of taking advantage of the 645z for gigapixel panoramic photography, there seems to be only one guy using the 645z (Joe Towner) and he has only posted 3 panoramas to date (and the gigapan website hosts more than 113,000 panoramas). But the details he captures are pretty amazing. Zoom in
here and you can recognize faces in the crowd at the far end of the stadium, using a 200mm lens.