I was initially going to say the levels lacked variety, but then I got to the 3rd level. That level was really well designed, I had to reset multiple times to figure it out.(unless I missed something obvious)
I also agree with some of the other comments that the character could move a little faster. Being able to pull furniture as well as push it would probably make the game feel less restrictive without really reducing the overall puzzle difficulty.
Woo… I found the cat!