Concept looks pretty dang boring to me. Oh look, canyons caves and rivers, how creative! Forerunner thingy, what an awesome idea! Seriously, it doesn't even look decent on paper. (err, pixels) I see no concept of gameplay, at all. I'll never understand why people post drawings of their work. To me a drawing of a map (well, a 2d one like yours) is only good for one reason, planning it yourself. Sure we can talk to you about gameplay, but I think you can determain that yourself. Models, models, models, people what to see models. Look, anybody can post a 2d concept, but only a few can created a good map from it.

I'm completely open to you proving me wrong though.