Here's my suggestion with the ratings...
If it is possible, make it so that there either needs to be a 'critical mass' or a certain waiting period (or both) before a game gets listed in the ratings. That way, you can hopefully miss a lot of the 'new' bump that people get from opening up a new game.
IMDB started doing this a while ago. It used to be the ratings would appear the day the movie came out, but it caused a lot of movies that had big fans who saw it early to be rated very high, and then to slowly nose dive off the top movies as more and more people saw them. To fix that, they implemented a waiting system. I feel like a three or six month waiting system to official 'list' a game wouldn't be a bad idea at all, and would hopefully allow people to really get an impression of it before rating it.
The other suggestion, not from a web site standpoint, is to develop your own interests based on what you are told, and then read through the comments that people made on those games, ignoring the positions and everything that they fall into. I tend to rely on IPDB's ratings a lot more heavily, as here it seems like people write one sentence and are done, while there people really dive into what they like or don't like. I've purchased a number of machines unplayed by reading through what other people said that seem to have similar tastes to me on that site, and only once or twice did I not pretty much fully agree with the ones who seemed to be like me.
Having said that, IPDB never keeps Sterns up very high for long, because every time they do they have a bunch of people rate them at like 3 stars anonymously. So don't trust the ratings -- everyone is different -- and read them for the content instead