I grew up skiing Stevens and have been a Baker regular for several years. I've also skied Whistler, Silver Star, and Sun Peaks several times each. Comparing Stevens to Baker is probably best since they are costal and both are day areas.
Stevens Pass caters to families and intermediate skiers and boarders. It has better snow than Baker on average, but not quite as much. It still is the #4 ski area in the US for snow totals, however. It is extremely crowded on weekends during January and February but is not too bad any other time. Weekdays are great.
The parking sucks. You have to walk a long way. They have a lot of area for night skiing, but mostly on blue groomers.
The advanced skiing is good and varied though it does not compare in size with the groomers. There is plenty to keep you busy for a couple of days. The best runs are off of 7th Heaven, Double Diamond, and under Southern Cross, though there are many more if you have a local guide or you just nose around. Once you get off of the groomed runs what crowds there are disappear.
Stevens is not a destination area. There is no lodging at the pass and not much of anything in Skykomish either, though there are a bunch of cabins there, mine being one of them, and one motel. It's 2 1/2 hours from Bellingham.
The operation of the ski area itself is corporate in flavor. Sort of a McSkiArea. The customer service is very good. The employees aren't high or distracted and they are doing their job professionally. It has none of that special character that makes Baker unique.
I'll be at my cabin for several days around Christmas and New Year's Day. Maybe I can give you a tour if you would like.