Human Trashcan
Banned
I can second the recommendations above for both DLCs. Hearts of Stone is the better overall story but Blood and Wine brings Geralt's story to a satisfying and surprisingly moving conclusion.
I was a little underwhelmed with Blood and Wine, but Hearts of Stone is easily a better storyline than anything in the base game, I think. Blood and Wine is good, but as an epilogue to Geralt's story it feels torn in too many directions. I'd only recommend that one if you really want more Witchering.