What's not missing is some quality writing, with strong characters and intense settings. I think the opposite is true, this is a real strength of the genre right now and it's very clear , if only from the sales figures, that these books have been ensnaring and captivating new readers. So what's missing?
1. Originality While there are a lot of original concepts in all of the above books, there are also a lot of unoriginal ones: like the walled city, the fascist police, the rigid caste system, the unfair division of wealth, the outcast hero and of course the love affair that spans all boundaries. It all makes a good literary drinking game to play at your book group, but the result is a kind of create-a-dystopian-society-by-the-numbers. As if to prove the point, random YA dystopia generators have sprung up here and here.
It's a kind of laziness - save time developing your own backstory by referring to someone else's. To be fair it's not unique to this genre at all, it's something that occurs throughout literature. The result is a backstory that doesn't feel credible and doesn't connect to the real world. An exception is "The Bees" where the walled hive and the caste system make sense as the main characters are bees.
2. Social Commentary George Orwell's "1984" was driven by the development of Communism into a totalitarian state, and the fear that this could be the future of the world. "A Walk To The End Of The World" by Suzy Mckee Charnas is a feminist novel taking male oppression to a seriously extreme conclusion. While the new-ish wave does seem to care about class or wealth inequalities, these feel like easy targets but there's no real attempt to criticise or satirise present-day countries, societies, governments or political trends.
3. Hardcore suffering Kurt Vonnegut's famous advice to writers (summarised here) includes the following gem: "Be a sadist. No matter how sweet and innocent your leading characters, make awful things happen to them, in order that the reader may see what they are made of." I'm not saying Katniss and the others don't suffer at all. But in all honesty I don't think she, Flora 717 or any of the new-wave heroes would last very long in Room 101.
4. Some curious omissions The Panem society, the Divergent scenario and many of the above settings, for all their fascist trappings, are surprisingly feminist. It's as if the overlords took a few years out of their plan to conquer and enslave the poor, in order to achieve total gender equality, apparently with minimum effort. Well done, dystopian leaders! Once again, "The Bees" is a notable exception.
So I propose to write a dystopia about a teenage girl growing up in a society where everyone is forced to read dystopian fiction from birth, who starts to suspect that, beyond the mysterious wall of dystopian books there might be some other mysterious reality, and who must pluck up the courage to lead a revolution so that her kin can enjoy (for example) Scandinavian detective novels. Cheers...