As a side-project as I write my science fiction stories, I've begun brainstorming on a fantasy story that's set in modern-day. It's told from the perspectives of several characters in a world where most supernatural/fantasy creatures exist. One of the major elements is a government organization tasked with dealing with supernatural crimes and rogue creatures as well as assisting some creatures into integrating within human society. It will change parts of the overall tone in the story depending on which option I pick. I'm thinking that this department is either behind the scenes, keeping mankind oblivious to the various creatures living among them or have the majority of these creatures out in the open, keeping some more dangerous ones locked up. My only problem with having the supernatural/fantasy world out in the open is that one of the characters starts off as a decently successful travelling magician (she eventually comes to the attention of the department). If we lived in a world where magic was part of everyday life, why would people go and see a magician to begin with? However, the story of a department tasked with keeping mankind from finding out about other live living among us has been done almost to death and I want to try something newer than it.
Could magic be part of everyday life, but most people aren't experts at it? Like, my car is a part of my everyday life. I put gas in it, I drive it, but if I need the oil changed I go to a garage, if it breaks I need a mechanic, if I want a new one I go to the dealership... being part of my everyday life doesn't mean I don't need 'car magicians' to help me with it. Would that fit your world?
The character isn't human, either so all the more reason for her to make a career out of magic. Hmm... Her particular species wouldn't usually appear in public in general and tend to keep away from humans. It is a species of my own creation after all. I was going to write that she thought she was the only one of her kind, but I suppose I can change a character's backstory a little for the sake of the rest of the story.
As a non-professionally practicing magician myself, I can say that the point of magic is not supposed to be convincing the audience that you have the magic to perform miracles without special effects. It's about the audience knowing for a fact that you use FX instead of magic and yet being dazzled by the FX anyway. There are real sights in the real world, but people still enjoy the "fake" sights of a movie theater. Likewise, if there was magic in the real world, people would still be drawn to the "magic" of a magician's FX, and mages might even be kept out of magicians' circles as "cheaters." There would have to be a distinction between mages' "power-Magic" and magicians' "performance-magic:" power-Magic might be able to accomplish tangible goals that performance-magic cannot, but if somebody knows that he is seeing power-Magic in a magician's performance, then he knows that it was done by breaking the laws of science that most people live by. If somebody sees a magician whom he knows not to have power-Magic, then he's going to be impressed that this guy was bound by the same laws of nature that he is but was still able to create something fantastic. Of course, there would probably be other people who don't care whether a stage magician is a "true" mage or not as long as the show is flashy enough, and this could then turn into professional rivalries between groups of magicians who do vs. groups who don't care about the use of power-Magic in a performance. I might not be able to help here because I haven't read/seen many stories of that type (the Watcher's Council from Buffy the Vampire Slayer, the White Council from the Dresden Files, UNIT and Torchwood from Doctor Who, and the eponymous Men in Black being the ones I'm most familiar with), but from what I have seen, most of the emphasis is on how humanity needs these organizations to protect them from the other races in the world. Maybe switch that around: "Humans can't even stop torturing each other to death, what do you think one'll do to us"? Less Spanish Inquisition and Birth of a Nation (protecting a "superior group" from an "inferior" group"), more Underground Railroad and Witness Protection (protecting good people from evil people). The Ministry of Magic from Harry Potter is the only example I can remember to have taken that direction, and even then it was only mentioned in passing rather than explored specifically.