As things stand today, it is not even a given that the Kings are going to be moving at all. Reportedly, there is a large conglomerate with deep pockets willing to keep the franchise in Sacto. And, let's face it, Seattle is going to acquire another NBA franchise long before any other potential - and there are not many - NBA cities. In other words, don't expect a franchise in Louisville anytime soon.
Cincy isn't a realistic option - new arena or not - due to the lack of a large enough corporate luxury box infrastructure to accomodate three Major League franchises.
As an aside, I do like Joseph's out-of-the-box idea of targetting an NHL franchise, though, it's unlikely that another NHL team will relocate anytime soon. Immediate future expansion doesn't seem to be in the cards for the NBA or NHL, either.