Four was my favorite by far, wasn't even close. The secrets of the Cosmere being teased here are just too much.
Three came next, really love the world, and the magic. These planets they are likely going to be very important in the future, I could easily see them being a regional power.
One was pretty good, but the only thing I care for here are the Aethers.
Two was the bottom of the barrel by quite a long ways, not that it's bad, but that simply by virtue of being Cosmere novels the other three are just too far ahead for it to ever hope to keep up.