Your wife's She’s Piste will be nominally dimensioned 112-70-97. This should be the "outside width" of the skis -- if you measure across the entire ski: base, edges, and all.
When you trim your skins, you will definitely want the metal edges to be exposed. After all, if they're buried in plush, they won't hold on our interesting snowpack. One way to make sure that they're exposed is to put the untrimmed skin on the ski 2mm off-center, trim along one edge (outside the metal), then shift the skin 4mm to the side, trim along the other edge (again outside the metal), then recenter the skin and see your steel edges gleaming on either side of the plush.
Your edges are about 2mm per side, I suspect (though Atomics can run thinner on some models). You'll thus be trimming the skis 4mm narrower the ski's dimensions. (At the tip, for your tip loop attachment, you'll be trimming even narrower.) You thus nominally need 108-66-93 skins. 95s will thus cover your entire base from tail through the waist toward the tip. At the very tip, you'll have 1.3 cm of uncovered base showing -- but again, you'll have trimmed your skin tip to take the tip loop, so some base showing is inevitable anyway.
Go for the 110s if you want; they aren't much more expensive. You may be able to reuse the skin material for kickers or for a ski tuning table. (If you're making kicker skins, try using detergent bottle material as the frontplate for your skins. Bright orange, and stiff but flexy enough to do the job -- and it'll take a 1cm nylon strap well enough to hold on.) Just be aware that you could get away with 95s if you prefer.
Kickers work well, but more for the touring aspect than for up-up-and-away yo-yoing.