@Xenocythe -
As Kevin just said, there's no incentive to join.
Your site is essentially a framework. There's nothing really going on there. There's nothing that I can post there that I can't already post here and get much more exposure.
You are giving away some stuff, however...
Quote: "100 unique, highly detailed, heightmaps
4 Seamless, tileable textures
1 Ready-to-use models"
Heightmaps aren't very interesting. It's not a bad giveaway, but nothing that will capture most people's attention.
There's no community, there's no incentive to join, and you don't have a product. You should have developed the site more before you released it. Many of the links are under construction, and that's unacceptable for a public release. Many people that will visit the site will not go back for a second look.
While I'm on the subject, the color scheme is pretty gross.
Quote: "The team request system is nicely crafted, and works great for anyone."
As far as I can tell the team request system doesn't work at all. All I get is a blank page that says 'Requests'
Come see the WIP!