in terms of reverse camber: don't slag 'em until you've tried 'em.
i rode a pair of first gen Mantras in 2005/06 as my powder plank. loved 'em. but they were also the first "fatty" i had ever ridden, just having recently switched from a 63mm waisted ski as my all-arounder.
2007 i switched out to Spatulas. WHOA! these things slay the Deep Powder. I haven't gotten 'em out in crud yet, but have been told they handle that and crust on fluff with equal aplomb.
At any rate, not to be a snarky, but simply stating "The new skis would be used exclusively for deep powder/heavy, deep crud" leaves a lot of room there.
Are you a skinny ski lover or a fat ski lover?
Again, regardless of your take on RC skis, I would say if this is a dedicated powder set-up you want to be looking at 100+, most likely in the 112mm range. But that's just my humble, unadulterated, and largely uninformed opinion (if I didn't have Spats as my dedicated deep powder ski then I'd surely have something like the Moment Ruby or Fatypus D-Sender or the Black Diamond Verdit or maybe even the Rossi Steeze or even the Lib Tech Powder or PM Gear Bro fatty (all 110-117)...
anyway, i'd demo once we get some deepness.