My advice would be to either produce and distribute porn, or drive traffic to porn sites. Those are the only two roles where you bank. I wrote an analytics subsystem for my company's properties and I saw how much their affiliates make. If you were even partially effective at driving traffic, you could clear $75k/year. Their top affiliates would come closer to $1M/year. These were just individuals (sometimes they worked in pairs) who were great at SEO and building links mostly.
The drawback to driving traffic is that the porn companies are constantly shaving you. You had to track each of your referrals very carefully. Though generally, if the affiliates saw they were getting fucked over, they just switched off their firehose and directed it to another porn company. That always resulted in a face-to-face meeting with apologies and increased incentive to redirect the firehose.
More interested about the traffic and backend (pun maybe intended) challenges in a big porn site. Advertisement has the traffic but porn is more interesting :)
The drawback to driving traffic is that the porn companies are constantly shaving you. You had to track each of your referrals very carefully. Though generally, if the affiliates saw they were getting fucked over, they just switched off their firehose and directed it to another porn company. That always resulted in a face-to-face meeting with apologies and increased incentive to redirect the firehose.