I've only watched The Arsenal of Freedom so far, and the new extras. I wished they'd gotten more into why people like D.C. Fontana left half-way through the first season. Was it all because of Gene and his rewrites?
Also, did anyone see the "Next time on Starrrrr Trek: The Next Generation" promo at the end of the third Stardate Revisited? Looks like we'll get a good insight in the Season 2 set into exactly what happened with Gates McFadden.