I fixed the thread title.
One thing to consider with Wilbur is that you can often get better results with hard-edged masks or with very noisy height fields than with nice smooth height fields. The smoother height fields make the erosion processes run straight down the slopes rather than wiggling from side to side. Sufficient noise will knock things to the sides. The amount of noise needed to get good results make it look like everything is destroyed on the first couple of passes, but it evens out fairly quickly. I also like to throw in a little morphological dilate operation to get rid of speckles and spikes that creep in.
How are you doing the lighting? Is it a straight bump map lit inside of your paint tool or is it a light map from Wilbur that's blended with coloring?
If you haven't looked at it, consider looking into the texture shading operation in Wilbur. It's based on Leland Brown's work and it can lend a nice air to the maps that basic hillshading alone can't (
http://www.shadedrelief.com/banff/texture_shading.pdf is a good set of examples; the UI elements are a bit different, but the ideas are the same). Adding a little bit of the texture shader effect to your other color modulation operations (e.g. bump mapping) in the paint program can give a lovely painterly effect that reduces the harsh lighting effects of straight hillshading.