I've been wanting to do something similar to this, to get an overworld idea of design going forward. This is wonderful inspiration!

I usually begin with mountains and hills, then on to rivers and swamps flowing out before I finalize the coastlines. Forests and the placement of cities is my last step before I think about depth of detail. Scale of perspective is a key factor, so nailing that down first would be a solid foundation.

I'm fond of your style as well, it has a softness that I can't quite explain. It's nice.

IR