Magic is one of my favorite things about a fantasy setting. You are not bound to the laws we know of and you can rewrite basic physics and reality to whatever you want. Also, building the world around it is extremely fun.
I like ping-pongs between harder and softer magic systems, but my favorite hard-leaning magic system has to be bending from Avatar. There are four elements, most people who can bend get one, and they can really stretch them out.
As for softer magic systems, I enjoy when it helps to make the world function. So far, I kind of enjoy the Owl House. Sure there are glyphs that harden it, but there are some branches like healing and construction that make it seem more like these magic covens are divided like labor guilds, rather than strictly element.
I like the theming of Vancian magic. Magic is this thing that was once extremely common, with millions of spells - but as the world has become more advanced, the prominence of wizards has waned. Without entire societies backing their research, the creation of new spells has come to a halt - and without large numbers of apprentices memorizing spells and copying them every generation, many spells are lost every year. Now there are only a few thousand spells remaining, and instead of working together wizards guard their knowledge from each other - instead of packing lecture halls full of students only a handful of apprentices are being trained at each time.
It's a take on Tolkien's theme of the magic in the world running out and being displaced by industry, but where Tolkien had only a small number of Wizards Vance had entire societies of them.