99.8% of the traffic you sent a paysite will not buy anything & thus cost you money. it's that 0.2% of the people that we all make money off
Contest is one of those things that no one can really put into words or lists as far as what's overused & what's not. I have 4 people reviewing my links & if one of them sees a lot of content promoting Joe Blow's Megasite then they might decline the submit. But that's not to say that the next Link List you submit to has not seen the content a lot & will list the site.
Believe me, I know it sucks - LOL