After many years with more serious read I got back to fantasy in September by starting with Wheel of Time, then all of Cosmere books where I finished Oathbringer just weeks ago with some 10 first Discworld books in between. Sanderson isn't perfect, but his writing improved immensely with each new book. I wouldn't really recommend anything other than Stormlight Archive and might be Mistborn era 2 unless person want to be very Cosmere-aware though.

Still his problem with Shallan is pretty much the same as he had with Mat in first of his WoT books and basically with every other witty character in every of his earliest books. He just wasn't good enough for writing some types of characters, but still tried to include them regardless. I think everyone will agree that he actually become better at this since most of people I talked with enjoy Hoid in SA.

I don't try to justify it, but I think it's not that easy to fix character like Shallan since her character was well defined in first book released in 2010. I guess what we can see in Oathbringer it's attempt to do that although not very good one.