Well as you said the objectifying of women is extremely annoying. I got into the biggest fight I've ever been in with a close female friend of mine once because I heard her sing a long to some lyrics I found appalling and degrading and she had to hear it for weeks.
But the general attitude is annoying. I hate tough guy acts, you know the "I n ever smile because people who smile are weak" look. You've seen the guys blaring rap music with sunglasses on looking deadly serious for no reason. People have tried to fight me for making eye contact and walking too close. Which is another thing I hate, violence. I hate the blatant disrespect for life and others well-being. Like someone scuffing your shoe is worth their life.
And I know it seems contradictory since my favorite bands have songs about sex and being tough. But 9 times out of 10 it's either not serious or just a song about teenage angst or lust, which I can relate to. I can relate to a bad mood and hearing Stive Bators sing "I'm gonna knock down the next hippy I see, then I'll be knocking down you, 'cause their ain't nothin' to do!" because it's not a serious thing, it's an angsty fed up song.
The money thing is annoying too, especially when they try to maintain both a rich playboy image and a straight out of the ghetto look at the same time. It sends all kind of the wrong message, kill and sell drugs to get out of the ghetto and then you can waste money and be a masoginist in the public eye! Another thing that makes the same kinds of messages about sex and drugs in rock 'n' roll less threatening is that rock 'n' roll is more about the music. It's more about the guitars and drums and the sounds. When the music is stripped down to a beat on the high hat and bass drum and a bassline then the lyrics and pointless messages take center stage. And everyone does the same dance to all rhythmic music anyways, which again goes back to the sex thing.
I'm ranting and not sure I'm making sense and I'm not making my best arguments right now so I'll stop. I've explained this very well before but I can't now, but good question.
It's worth noting I don't have anything against more productive rap, I even enjoy the stuff I don't find repulsive.