i considered myself to get only a pair of ski to ride everywhere, pow and park, this is the reason why a bought a '09 volkl bridge...
they have mid-fat waist and have a wide shovel, so they're pretty good in pow, but on the other side they're stiff and true center is set quite back, therefore it's not the best choice for park riding (even tough there's an edit here on NS of Liam Downey using them in park with so much style
https://www.newschoolers.com/web/content/news/news_id/1843/ , but he's so good it couldn't be anything else)
this is the reason why i've changed my mind and come to the obvious result that 2 skis is better than 1...
sure it get expensive, but if i had the money i would no doubt get myself a pair of moment rocker and a pair of moment bibby pro (a sick combo imho)
so a good idea could be get a cheap park ski, like line afterbang and a fat backcountry one
with this said, i must agree that '10 k2 kung fujas with the new schizo system (allowing to move bindings back and for 6cm) could shred really well both pow and park
http://www.untracked.com/p3031c13b37-10_k2_kung_fujas_skis_w_marker_griffon_schizofrantic_binding.html