Those rivers look very, very good! I know it will probably be hard to change, but some higher rivers are wider than lower down. They probably get wider because of the valley width or slope at that location. For stills you can choose a good spot, for animation it will be harder to circumvent the 'wrong' rivers. Btw. Daniil, now that you're here; did you check alpha forum? I think the latest is an older version than the one before.