I have burned through a lot of Brandon Sanderson's work, and literally a ton of other fantasy in hopes of finally setting the rules for my magic system. Still have a few more of his works to get through before I can consider my research complete, but my magic system for the most part is developed.
I've only ever read the mistborn trilogy and the follow up to them as far as Sanderson goes. I enjoyed them but fantasy normally isn't my favorite genre. Anything else by him I might enjoy? Supposedly he's going to write more books in the mistborn universe eventually but I'm not holding my breath.
Mistborn is a great piece of fiction with one of the most inventive magical systems I've encounter outside of Robert Jordan's magic system. If fantasy isn't really your thing Sanderson may not be your thing because that is what all his fiction is about really.
He by far has the widest reaching epic I've encounter. His creation of the cosmere is something that I couldn't even imagine doing with fiction. The Elantris series, the Stormlight Archives, the Mistborn Series, The Warbreaker series. The idea that in some way all of these worlds are connected, and somehow share elements is unbelievable. When Sanderson finishes his work the Cosmere is going to be the largest epic collection of all time.
See, but that is part of the system. His three laws encompass what magical systems have to be about. The magic itself, the limitations of that magic on people, and how that magic links with the world around it. It is because he builds magic systems like these that they work so well.