Atelier Hachifukuan does nice bondage work, but I prefer his releases under the Nightmare Express circle. His themes are edgier and his endings much darker under that label.
Ya I agree very much with you, but lets not forget that Atelier Hachifukuan also has a very good series that is Superheroine in Distress. Also in some of their works they may not give a dark ending to their heroines but that doesn't that the ending is a happy one!