I may have some explanation as to why some players get more hate than others.
I myself used to get hate mail almost hourly when playing and it wasn't like I was all that good back then. I got a heap load of bad rep too and was at a loss as to why because it wasn't because I played in any of the really annoying ways players often do (camping etc).
Then one day while in a totally random lobby for the first time with a mic on (I had just left a party and still had it on) a player mentioned my gamertag. It suddenly hit me that my gamertag was inflaming people toward me because it had a slight air of superiority about it.
800 MS points later and my bad rep became pretty much stable and the only mail I get is when I go extremely positive in a game (I have since improved somewhat) or when I quit due to lag and someone notices which is rare (the people noticing, not the quitting).
I still get those bored messengers speculating at my sexual preferences or trying to get some kind of vengeful message back in order to start a pointless to and fro of hateful appendage measuring. But it happens far less than it used to. I guess now I blend in?