That's the best looking tire cover I've ever seen! I wonder, though, if making it out of rope or some other non-yarn material might make it sturdier. Unfortunately, it might possibly be burned off in places by the end of summer if you're in Texas as your license plate redo suggests!!
It's a wonderful idea, and you did a great job creating it. I sure hope no one is stupid enough to steal it (put a lock on that baby, maybe?)