I just binge-watched all six seasons of Lucifer. IMO this is one of the very best TV series ever. In fact it noses out Sopranos for the #3 slot on my All-Time Best List. Only Breaking Bad and The Wire are better.
Yes, all four of those series deal with crime. No, I am not particularly interested in crime. But crime or criminal investigations lead to suspense, good dialog, and a focused story line.
Police procedurals can be fun if they have something extra: eccentric lab technicians or consultants, humor, a little corruption, pizazz (like setting CSI in Las Vegas). Lucifer has all this and much MUCH more. Does the eccentric Sherlock Holmes as a consultant make a detective show more interesting? How about a consultant who's on a vacation from his job as King of Hell?
Sure, the premise is preposterous, absolutely absurd. If you're one of those quibblers who thinks Casablanca is ruined because the "Letters of Transit" are unrealistic, then you might want to skip Lucifer. Even worse than the supernatural might be that this show will, eventually, tug at your heart-strings. The cornball gets extremely sappy.
But these "flaws" are actually virtues! Unrealistic backgrounds and sentimentality are common ploys in good cinema. This show goes all the way. It gets 8.2 IMDBs and 88 Tomatoes. It deserves much more.