Okay, only major thought.
The northern peninsula that is kind of shaped like the alien's head from the Alien Movie franchise... It has a BUCKETLOAD of lakes and NO streams/rivers. Results: this place is a swamp OR this place is packed full of mountains with underground rivers in them. Both work just dandy, but you'll have to plan that area carefully.
Plus, just be careful in some areas, this is looking like a very wet, river-filled world. Otherwise I don't think the River Police will get you.