I think that to have a good server you must truly be into it. You must look at it from the perspective a player does, look at what they need to not be frustrated, to know the game as if this is the first time playing, as if no other server exists and yours is the first they played. The ease of play, access to information and abundance of information/things to do is that attracts me to a server.
Stability, Economy, Ability to seek help and the knowledge of other players, active, helpful and dedicated staff.. and of course the kicker being things unique to that server that will keep me there.
Unintelligent players who can't speak a lick of english that I can not converse with deturr me from a server if there are an abundance of them.. If they are in small quantities I don't entirely care.