Adsense site get stung every update. More are there waiting on the sideline to take the place of the ones that get booted. It just won't be you that makes the money. It's a hard world but thats the way it goes.
Sure, as you said don't bet the farm on one advertiser/site. That would be a slightly daft move. You are bound to get bitten by something somewhere along the line. But, with a little bit of imagination and your fingers in a few tasty little pies you can make a good living from AM. CJ are not the best affiliate network and do not have the sole rights to the merchants. By this I mean if your merchant doesn't perform on CJ you may find them registered on another network where they appear to perform 100% better.