I’ve been trying out a few Terrain Generators and I think WM is by far the best at least for what I am after. In saying that there are a couple of features I think would be nice to add that I have seen in other software.
Instant Terra has the ability to hand draw a Curve so in WM in the Curve properties it would be nice not to have to use points but draw a curve which might allow a little more control over subtle changes.
The other feature which I found nice in Instant Terra is the ability to click on the Input and Output pins to a Node/Device and see the actual input/output in the view. This saved having to hunt down the linked nodes and to also check the input and output was what you wanted or expected.