(Hummm, neat idea, but uncertain on photos wrapping around the corner. The frames could meet up on the edge, but think the frames still might be best if they met in the corner but that each wall had its own photo frame.
Although the tone of the doorbell is not as monotonous as before, it is still different from piano. However, China's designer Li Jianye gives us a piano doorbell. This product has several piano keys which allow the guest to play what ever tone he likes.