Simply having a thief enter your house while you're not there and your stuff just disappears, yeah.
But if, upon returning to your house, a quest notification pops up and you have to find clues and talk to people and stuff, it could actually be a really cool variation from the typical side quest. You'd be able to get all your stuff back and have a cool experience along the way.
It should probably only happen once though. It would probably get annoying having to do this often.
I agree that a quest in which your stuff gets stolen could totally work. It's just thievery as a random event that would appear broken.
This was talked about a lot when Beth first started talking about radiant AI back in the day. Similarly, the question was brought up regarding whether NPCs should get into disputes and kill each other when the player wasn't around. The possibility was there with radiant AI, but Todd said they cut it because it just felt like a random glitch in the game. The player would come across corpses in town, not know how or why they got killed, and figure something was wrong with their game. Quests would get broken due to events you had no control over.
With some of the changes in Skyrim (such as relatives taking over for dead NPCs), I could see work-arounds for some of these issues, but I think the core problem remains. Without a quest to put things in context, players don't make the connection that vanishing items are due to thieves or random dead shopkeepers are thanks to some local dispute. They just see the aftermath and feel confused, and that makes for poor game design. The player has to feel in control - if not causing an event, they at least have to witness it so as to feel connected to the world.