God yes! I use a laser level to hang pictures, and it drives me crazy being in someone else's house or a doctor's office or somewhere and seeing uneven pictures. I HAVE to level them. I want to rehang them so they're spaced properly.

As far as unevenness and dents in walls and such, I feel compelled to fix these things too. On a positive note, obsessing over things like that is why I'm a contractor today.