Stormlight is his first go at epic fantasy (other than finishing WoT) and if you don't mind large, unfinished series is a great read. I might recommend that you read Warbreaker at some point before reading Stormlight 2 or 3, as there is a little crossover and adds a little nice background (more so for stormlight 3). If you start to get into Sanderson you'll learn about the larger "Cosmere" and how everything is connected.
It definitely isn't required but if you are like me and love all the little nuanced references and easter eggs hidden in there then I would read it. Its a standalone and a fine read on its own. The same podcast also has a series for Stormlight, mistborn, and a few other series. I like the podcasts that are people sort of reading along with me or just reading a book and reviewing it. There just aren't that many out there, especially good ones.
I'll definitely pick up the Warbreaker next, thanks for letting me know.