LEGO Pinball would definitely be fun. And it's in an interesting "between" zone of original, but still licensed. They could create their own theme utilizing LEGO if they wanted. It wouldn't have to be strictly the LEGO Movie.
As far as Disney licenses - I'm fairly certain Stern does not have exclusivity. And from Disney's standpoint exclusivity doesn't make sense. Why go exclusive with Stern, who will put out probably 1 movie license in a given year when you could spread the pot and get 2+ movie licenses out in a year. Think about how prolific Disney is. They have their hands in EVERY cookie jar. There are Disney cups, oven mitts, Christmas stockings, shoes, candles, phone cases, salt and pepper shakers, band aids, erasers, and every other type of trinket.
Disney is everywhere, I don't see why they would draw the line with a single pinball company.