[moderators - rambling follows. if this is against the forum rules, please remove the post]
regarding the size: I don't know why CaNi feel obligated to build these gargantuan sized FF bodies - apart from feeding the common misconception "that guy has a Big Black Camera, he must be a PRO". ok, there's larger mirror box (is it, actually? depth-wise?) and larger pentaprism, what else? does a physically larger sensor require a physically larger processor?
. I don't see a reason, why Pentax's supposed FF would need to be bigger than K-3. that's just me, perhaps, but N D800 and C eos1x are ugly, ugly cameras. did they do it on purpose?
after all, pentax has built nice, compact 35mm film cameras, and these bodies needed to store FF mirror box, prism, and two spools for film. and the battery. I still think, that MZ-S is one of, if not the most beatiful 35mm cameras ever built. precise, angular, purposeful, sleek lines, nothing redundant, "ripped" like a gymnast, who needs to be strong, but who can't afford an ounce of redundant weight. and weird enough to stand out of the crowd.
OTOH, marketing trumps common sense any day; significant - if not the largest - market share are aspired amateurs, of which most are men - or at least I tend to believe so - and for men, "bigger is better" is chiseled in their subconscious. more megapickles, bigger cameras, huge, huge lenses = more happiness and better pictures, at least till someone with even bigger camera and lenses appears on the stage.
As much as I think that K.R. [sometimes] is a pretentious snob, he got it quite right with "equipment measurbators".