In TV, books, and movies, it seems like every detective/PI/cop deals with the big crimes--murder, rape, art theft, etc. So what about one that's about cops/detectives who deal with minor crap, or are traffic cops or something? With the focus being a lot more on the people rather than the cases. Stick in a supernatural element, preferably a lot more understated than in other shows: each of them has a supernatural secret and doesn't know their partner's secret (though it doesn't drag out for too long; eventually they find out because otherwise they just look stupid), but most of their cases are normal, mostly boring cases, and their supernatural secrets only occasionally affect their lives. Put a limit on how often they have to draw their guns, and how often the supernatural causes more than minor irritation, and stick to it.