Here I've selected my favorite 4 thumbnails from the past few sets. 65-68 is a combination of the crystals and lava described in the first extract (which I sketched out separately first).
I can see from this set my favorites emerging to be used as my final pieces. However, as much as I like no.69; I'm not entirely sure it will alongside such an impacting orange mix and green. An experiment would be for the best before I set on that if I want to use it as a final image.