I have done a quick trial of how to use the new Terraprints to create rivers. Below blueprint is really just a trial to get some feedback of how you think it could be used to create rivers more easily.
The Blueprint is quite big and there should be sufficient terrain if you want to place it. Some smoothing and of course decoration, adjusments, etc are necessary depending on how you like to have it.
If you think its a good start let me know and i try to refine it a bit more, as well as adding shores, springs, river bend, etc.
Ich habe mal einen schnellen Versuch gemacht um zu sehen ob man die neuen Terraprints nutzen kann um Flüsse zu bauen. Natürlich benötigt dieses Flusstück noch einiges an Feinschliff damit es in eure Welt reinpasst. Lasst mich wissen ob es für euch passen würde und was geändert werden muss. Dann versuche ich es anzupassen und noch mehr Teilstücke zu posten. Flussufer, Quellen, Flussbiegungen, etc.
Maybe you could make them into segments so people could make custom rivers. Doing straight sections, elbow joints (L-shaped), wavy sections, etc. and then people would piece them together like Ikea furniture! 
