V-W-X
V is for... Villains
Yes, I considered saying V is for vampires and just swiftly moving on, but I started this god damn list and man will I finish it. Also, Whedon is great, amazing even at creating awesome on screen villains, which is a great omen for The Avengers 2. Affectionately named Big Bads in the Whedonverse, there have been many, many classics. The Master is old school but scary as hell; The Mayor was so nonthreatening but at the same time purely evil that his character was pure genius; Adam was slightly lame, but watchable; Glory was on another level, a total female bad-ass who just happened to be a god- yes please. The First and Caleb were also terrific creations. But Whedon's great strength was in showing the heroes become the villains, demonstrated perfectly when Willow goes all Dark Phoenix and even better in season 2 when Angel looses his soul. Though Loki isn't a Whedon creation so he can't really get the credit, the dynamic of a villain who is part of the heroes family and has the potential to be good once again is right in Whedon's comfort zone, and his history with this sort of villain probably helped greatly when it came to writing The Avengers screenplay.
W is for... Willow
Because Willow deserves respect. Willow is one of Whedon's most universally loved and cherished characters. The characters journey from Season 1 to Season 7 is also probably the best transformation (and most realistic) a character has ever shown on screen. From a lovable seemingly straight nerd to a bad-ass wiccan lesbian who could easily (well, not too easily) take even Buffy in a fight, this transformation may have seemed forced and unnatural on any other TV program, but somehow this transition on this perfect show is seamless. Credit to both Whedon and Alyson Hannigan for making this possible. She is to this day the greatest witch to appear on TV.
X is for... Xander
Thank god for Xander and Whedon's choice of strangely spelled nicknames. If Xander had used his real name Alexander in the show, I would have had to try to fit Xylophone somehow in this list. Xander is the needed human character we can all relate to on the show. Unlike lesser shows (though still good) such as True Blood where all the characters these days seem to be getting superpowers of some sort, Whedon kept Xander human throughout, in order to keep the show grounded. Xander is the way into this show for a lot of the audience, particularly the male audience who don't so much like the idea of watching a show all about girls. Although the character doesn't evolve all that much throughout the series, and has the least interesting stories (apart from his relationship with former demon Anya) he is the sweetest and most of the time most easy to love character who remains mostly good throughout. He is one of the only central characters apart from Giles and Dawn (who also remains human throughout despite being a mystical ball of energy) who doesn't at one point in the show try to kill everyone. Having said that, there is that time when he is possessed by a Hyena and eats a live pig, so maybe he isn't all that relatable after all.