We went for a friends NYE vacation, with skiing at Mt Baker included. We loved being that close to the mountain! It made getting up in the morning to drive up a lot better. Having the hot tub for after skiing was a dream, we absolutely loved it. Make sure you are paying attention to all the notes around the house, they are super helpful!
In terms of space - honestly the pictures don't do it justice, its so cozy yet spacious. We never felt crowded or overburdened. And all of us had great sleeps.
One downside was we were there during a cold snap, and turned the heat down at night in the main living room.... which made it freezing when we woke up in the morning to make breakfast. So recommend not turning it down too much!