Actually that's how I use it too. Get the drawing to broadly look like the result you want then start it passing through Wilbur, then fix it your raster program, then run it through and so on until I actually get the result I'm looking for. The biggest problem I find is Wilbur cutting diagonal or straight lines on areas that get very flat, and those are most of what I end up fixing. The other option is to get height maps from real data either from earth or other planets and then mix and match to stitch together what you want, then run it through Wilbur.