I caught Chappelle as Laf/Jef this past week, and while his Lafayette wasn't all that memorable (as I've found most to be, with the exception of Diggs), his Jefferson was something else! Like, flaming homosexual campy Thomas Jefferson. I personally loved it, since he milked the eccentricity and humor of the character as much as an actor could possibly do. As for keeping Jefferson as Hamilton's antagonist/foe, I still think it worked—during the rap battles and "Washington on Your Side," you could see him realizing that he had to deliberately put aside his crazy personality to go toe to toe with this punk. I thought he was excellent.
Ryan Vasquez was also on for Aaron Burr, and... HOLY CRAP. He was a REVELATION!! I'm hesitant to say that I may have even preferred his Burr over Leslie Odom, Jr.'s. He was remarkable, and I hope he gets moved up to the role full-time whenever Daniel Breaker leaves.