I think a dedicated ratings board of some sort would be a neat idea, have age ratings be handed out by them, their real humans, this would prevent people lying about their age ratings. This is a common issue on GameJolt, and quite frankly, I think they got rid of the Mature tag, banning illicit games altogether. Now, don’t quote me on that, but I think I saw an email about that.
Either way, I think it would be a good idea to appoint volunteers into the position of “Age Rater”, allowing them to view games that weren’t rated, where they can look at the project, test the games, and make an informed decision as to what the game is. It would help get a grasp on what the games are, and we don’t have to see dozens of lewd games on the home page anymore.
I know it’s a big, complicated change, but I feel like it would serve as a positive change, while not having such a large impact in the community.