I'll think about it, but yeah, actually the idea was that you could generate villages until you got the right one. Generation takes a fraction of a second, and it's not like there are a huge number of parameters, so it shouldn't take 3 hours.
If you have specific requirements for a river or a highway, you can first find a map that satisfies those requirements ignoring the village itself. Then you can "Reroll village" (via the context menu or by pressing Shift+Enter) to get a good distribution of secondary roads and houses.