With the new interface, the show solution button doesn't ask "Are you sure?", or anything. I just accidentally clicked show solution, and it didn't stop me like it did before. I think this is a problem.
Also, what's better about the new interface? Moving the buttons around just seems confusing.
Other requests I have: 1. Show rating of problems not in your set.
Show point value of problems not in your set.
Be able to keep track of problems not in your set (bookmark, or maybe put under activity when solved).