Just remembered one thing:
Not a Vue tool but rather a Vue companion, I find GeoControl a "must have" for true Vue'ers. The quality of the terrains is far superior to what Vue can produce natively. Furthermore, you have lots of different possibilities.
http://www.cajomi.de/GeoControl/geocontrol.htm
It's not too cheap so in case you want to take a look at some examples, I have lots of images in my gallery with Geocontrol generated terrains.