I'd love to see some more detail on the ancient frozen ruins of a civilization that pre-dates the Azlanti and Aboleths. I find the idea of something that ancient a little terrifying and REALLY interesting. Anything on the the upper frozen wasteland that's above the Crown of the World would make pretty happy actually.
But yeah, older than ancient ruins in a place that's virtually uninhabitable? I'd buy that.
Link for the interested. It was referenced from the Inner Sea World Guide 206-207.