I think this Marvin may be a work of genius. One of the complaints a friend of mine had about the BBC TV series rendition of Marvin was that he looked utterly miserable. There was no way this could be a design for a robot with Genuine People Personality, the future of domestic androids.
This design does look like it could. But it also looks perfect for slouching and looking miserable. Done right, it could really look like something that was meant to be cheery and ended up miserable, and that's not an easy mark to hit.