Okay, I just have to point out how fun and satisfying it is to watch the elements break after I've successfully swung the safe right where I intended it to go.  I think there's a ton of potential to play off of that satisfaction here with some extra juice (screen shakes, loud crash noises, etc). 

The physics you have here with the big bulky safe lagging behind lends itself really well to a mechanic that is easy to learn but still hard enough to master to make for fun and interesting challenges. Kind of like the ball and chain in Zelda Twilight Princess. This game also has a super fun "Crazy Taxi" type feel to it and I could totally imagine some really silly hectic music accompanying it to drive home humor in it. I'd love to see the idea pursued further. Nice work!