OP, if you are a group of advanced skiers, you'd probably enjoy Beaver Creek as well. Quite honestly, Vail has plenty of terrain and on a powder day (when you know how to stay ahead or away from the crowds) it can be great and when there isn't much fresh it can be a groomer paradise, it is a bit boring in spite of its size.
BC has a lot more interesting terrain made ever better on a powder day. I like Copper a lot but don't ski there out of inconvenience (3 busses instead of 1 to Breck). It has lots of bowls, tree and extended, moderately steep pitches. Keystone just doesn't cut it for me. Loveland is fun with good steeps and big bowls, ditto A-Basin. Breck has a lot of steeps, trees, bowls and groomers. Despite my previous post, it does get busy on weekends most of the time, but the wary and the informed can usually avoid the crowds even then.