It's easy enough for me to share this stuff at the moment (and to get the data) so it's not too much work for me. It also forces me to document a bit more, so I won't be in such a hole the next time I want to update stuff. I think it's also good to get people working on real scale terrains so they can help me with my other problems
I've nearly finished the update for this data set.... My efforts on the train this morning.... ->
This is another image from my composite terrains with 4 surface layers masked by raw images created from the canopy and landcover data (canopy and white, grey and blue colours from land cover). The landcover masks are intended more for controlling the distribution of other surfacing/objects so you still need to sort out the variation within this distribution. Their inclusion here is purely to preview the distribution. The canopy image on the other hand makes a useful density shader, although I'd add in some fractal variation if you were going to use it for surfaces.
I still have one more terrain to create to provide the padding around the (which is why I chose a lower camera angle) but the 30m NEDs I need for this are hiding on me and I may have to download them again. Once I have that I'll release the updated terrains and supplementary images. There is still some stepping in flat areas visible here at the bottom of the image so they will need some displacements to disguise them.
All of the terrain within the canyon is at 10m resolution, and the final TER will provide padding to a width of 160km for the same file size as a single 8193 TER.