I don't study it very strictly, but I take mental notes, at the very least. It's the kind of thing I'm used to noticing.
It'd probably be pretty boring for him. Angels generally need a human vessel to have any sort of effect on Earth, and vessels are supposed to consent - although the portal has a bad habit of skipping past that step, and Michael hasn't answered me about that yet. But even if he left this one alone, there are a lot of people on Earth, he doesn't only have to pick from us. There are enough religious people around that he'd probably find one willing to take him eventually.