Replying to Ski beta for a clueless Aussie

ok so I've only skied in 'straya (read: hard icey shite, no powder)... buut I'm heading to Canmore/Banff for the winter real soon & I *need* some help about what skis to get.

how fat are ppl's ski's in the Rockies? how fat/stiff do they have to be to avoid sinking in the snow?

I'm 186cm & 72kg (umm, 6'2" & 158lb I think).

Not really interested in skiing parks, want to get better at big lines, ski everywhere, all conditions type thing. Looking for an alpine touring set-up so I can go back-country also.