skiing pow isn't that hard. you just go. we could have different definitions of big mountain, but all the times i've skied the west (which, admittedly, isn't that many), i haven't found a single trail that was remotely challenging. including bowls and such, which is probably as close to big mountain as you can get without leaving a resort or going out of bounds.
skiing on the west coast doesn't teach you to ski on ice or to use your edges properly or how to ski tight, technical lines through the trees and such. for my money, the west has better skiing, but the east is harder. at least as far as staying in a resort goes.