And I'm saying go ahead and make your reviews pay-to-view if they're really that good... No Joke. If that's what you do (I really have no idea, but it seems to be) then ban GoogleBot so they don't have access to your reviews, make the reviews pay-to-view and let word-of-mouth and quality take care of you... IMO: You'll know what they're really worth to people if you do.
If you can't then IMO you should rethink what you're doing. Sorry for the dose of reality if that's what it is, and I wish I could say something different or give you some better advice, but free traffic from search engines IMO is drying up and IMO it's not likely they're going to 'rain visitors' again any time soon.
The more visitors they take, the more they make and it's an ugly spiral for everyone else, because once they set a standard for a level of revenue they CANNOT go back, because they're a public corporation... They MUST INCREASE REVENUE. It's their sole obligation as a publicly held corporation.
I have sites which are noindexed and some which only allow the home page to be indexed, and slowly but surely they are developing traffic WITHOUT GOOGLE because they're unique and serve a purpose IOW people seem to like them.
I'm not just telling people what to do, moving away from SE dependence is something I'm doing...