I agree with those (and would add my favorite one ep character is Dr. Lazarenn from Confessions and Lamentations). I would add the music to the list--what other show had a soundtrack written for each episode? Also the speeches--there were so many that remain in your head: Delenn's in Severed Dreams, G'Kar's "We will be free" in The Long Twilight Struggle, G'Kar's farewell to Sheridan and Delenn's farewell to the station in Objects in Motion and Objects at Rest, the Declaration of Principles, Sheridan's resignation from EarthForce--this could take all night!
Also one silly thing that I really liked but wasn't terrifically important: their quarters. I know, weird. But they were all so different and expressive of their personalities. I go back and check out the art, and the lighting, the views from the windows. OK, it is weird. Must be my interior interior decorator coming out....