My favorite episode of the season (and whole series) would have to be Hot to the Touch. I know it didn't have the emotion that I Remember You did, but it was still emotional and really good.

After that is Burning Low, I Remember You, Sons of Mars, Princess Cookie, Ignition Point, Daddy's Little Monster, Reign of Gunters, Return to the Nightosphere, Goliad, Lady and Peebles, The Lich, King Worm, Card Wars, The Hard Easy, Five Short Graybles, You Made Me, BMO Noire, Beyond this Earthly Realm, In Your Footsteps, Gotcha, Who Would Win, Hug Wolf, Dream of Love, Princess Monster Wife, and Web Weirdos.