Steamboat

Ever since going to Steamboat 3 years ago, I have made it an annual trip. I would say it is an ideal location for beginner and intermediate skiers/riders, as there are tons of blue trails and one is sure to find something to suit their ability level. I can't speak to the quality/steepness of the black runs as I only ski the easiest blacks.
Steamboat is known for it's powder and tree skiing and there are places that even lower level skiers can enjoy some easier trees.

The base area is not flashy, modern and slick, so if that sort of thing is important to you, you may not enjoy Steamboat as much. However, Steamboat's lack of pretentiousness is one of my favorite things about it. That and the lack of crowds and minimal lift lines.

I have had a good experience with the ski school as well and was lucky to find an instructor I liked my first trip there and we've been able to ski together for each subsequent trip.

I find the free bus service to get around town very convenient and for a small town, they have a nice wide range of restaurants.