Never skied the mojo 90...
The PE is a great all mountain twin. Very good float in pow for its size. Stiff enough to carve RR tracks, even on icy manmade snow. The PE holds a good enough edge on east coast ice, but it isn't close to a well tuned SL radius carver. The bump performance of the PE is very predictable and skis bumps really well. The PE's feel is not very damp nor very lively. When I first got on them I thought the feel was fairly dead and bland, but after a while it started to grow on me.
I think the one trouble spot for the PE is deep lumpy cut up and crusty sunbaked crud. The PE is not going to slay (the nastiest) crud confidently all day long like a damper ski would, but it will motor through if you drive them. The PE is also not the most well made ski in that the top sheets seem to really get torn up easily just form skiing on them and the bases are fairly soft. Still the skis are fairly easy to ski in most conditions. I can't really think of a more capable all around frontside ski for UT and other high snowfall areas since the PE can work well in medium pow, medium crud, bumps, groomers, and park.
I think a sheet of metal would ruin the feel of the ski. What it does need is a 184 or 189 length. I agree that at 179 the ski does not feel super burly, and if you want that in a ski, you should look elsewere from the PE or the Mojo 90.