The rating system would be pretty pointless, I think. The creator and his friends who join will vote 5 stars, people who are interested will probably vote 5 stars, and very few people who read them and don't care to join would actually bother to vote. It'd just be high ratings all around, thus negating the point of the system. Alternatively, I could see some dickhead GMs going and 1 star voting all other threads just to make his look better. Mahz has previously talked about doing a system of tags to make searching for RPs be easily done though filtering for what you're interested in (such as selecting the Fandom, Vampire, and Romance tags to find Twilight and similar RPs, for instance), which will be much better for sorting through the tons of RPs because it'll be based on your interests rather than a generic voting system.

As for like/dislike systems, [url=http://www.roleplayerguild.com/topics/4287/posts/ooc?page=1#post-62029]Mahz has said[/url] he's cool with a like-only system, but having dislikes be part of it would be shitty and lead to bad things.