I'm messing around with the free trial and so far it seems like I'm going to need something better suited to smaller areas. The mod we're making only takes up... well... honestly distance is kind of a tricky subject in Elder Scrolls games, but let's just say it should take the Player about a half-hour in real time to walk from one side to the other, so let's say four square miles.

Using the Planetary Bombardment option in Fractal Terrains 3 results in some craters that I would probably describe as a cross between "hilarious" and "socially awkward."

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I'm going to try messing around with the erosion options in FT3 and Wilbur and see if that gets me anywhere, but frankly I'm really starting to suspect that I'm going to have to pay someone for this. Any takers?