Just wanted to comment on this part. I really have no idea what a "true derm hospitalist", but I assume it refers to someone in an academic center who sees a lot of inpatient consults and perhaps admits some patients. Even these people don't have what any reasonable MD would call "pretty rough hours". In fact, I would go as far as to say that no academic dermatologist has "pretty rough hours". Perhaps there are a few exceptions here or there, but I'd like to meet an academic dermatologist that averages 60+ hours/wk in the office/on campus.
All of the dermatologists that I know that work a lot of hours (60+ per week is my arbitrary cut-off for this) are in private practice (normally their own practice) and they only work so much because the choose to. They are very well compensated for the work, and they do have to spend time managing their practices.
All of these people could choose to work far less and still make tremendous amounts of money, they simply choose not to. One of the nice things about derm, as others have mentioned, is that we have that choice.