What are the ages in your family, and what are your families desires for activities when the lifts close? On what you said about what you want from your skiing portion, Crested Butte is a good choice, but it's kinda isolated once you are there for after skiing. Sounds like you got a Mom who may want shopping and stuff to do when off the hill. As far as powder goes, it's just a luck thing for the most part. Either it snows or it doesn't, however, some place get more than others and different kinds of weight to it. When Steamboat gets it, it's crazy good.
Another option is to go to Summit County, CO. It has about 7 areas all within 45 minutes of where you stay. Copper is cool as a family something for almost everyone. Breck has legendary park and terain. Vail is just west less than an hour for your Dad's mogul fix. Keystone and more. Another little factor to summit is that you can buy a seasons pass for Copper and Winterpark for about $300 if you are taking a longer trip and want an excuse to go back. Copper and Winter park are a bit apart, but you could hit Winterpark on the way in or out (closest real resort to Denver Airport) and ski the cult classic Mary Jane. I also think that pass gives you Fridays at Steamboat as well. This plan would be a lot of driving and/or switching hotels.
For families (I have a family, 3 kids and a wife), I feel Park City, UT is the best family vacation destination I have been to. I usually was there in the spring, but we did score one powder day that is likely my best day ever with it on a last weekend in March. It's a cool town with three areas all within 10 minutes of each other.
Hope that helps.
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