Phil, here is what I know. There certainly may be others that know more about these mountains than I do. If I don't mention the hill I don't know anything about it.
Mission Ridge: Often suffers from low snow but when it does get snow it is great. Being on the eastside of the North Cascades crest the snow is usually really dry. Some pretty good in bounds hiking in the Bomber Bowl.
49 degrees N: Unless they have changed things this year nearly half of this mountain is not open mid week. Now owned by the same people who own Silver this place still hangs onto its mom and pop attitude. Once again snow coverage can be an issue but what they get is really nice. Lots of terrain and good tree skiing.
[Schweitzer]: Yes, has gone upscale but not so much to make me not want to ski it. Lots of variety in terrain. Generally better snow at 49 and Mission but generally more of it.
Silver Mountain: Lots of varied terrain and good snow. Lots of terrain and it still has a low key vibe. Crappy grooming so if it is a groomer day go to Lookout Pass instead.
Lookout Pass: We love this mountain, mom and pop and great grooming. Lots of snow. Not a great amount of challenging terrain but some fun trees.
Bridger: Have not skied here but will be Feb. 5th or 6th.
Brundage and Tamarack: Once again have not skied here before but will be Feb. 17th and 18th.
Have fun, sounds like a great trip.
Oh, if you have some flexibility Mt. Spokane is another low key area that can have great snow and has a friendly vibe.