Anthony, that's good to know! I had also backed Planegea 5e, which is another prehistoric setting, but now that you're mentioning tribal and low tech, it sounds like I could maybe use this terrain for postapocalyptic settings as well! (Of course, if Modern wins, that would work for some apocalyptic settings at least, and maybe even some early cyberpunk.)
As you get to making these, it might be good for backers to sound off about what they're going to be playing with the terrain because that may feed into your ideas for new terrain pieces.
These terrain sets do take some thinking about where they could be used, because I was just thinking the other day that I might be able to use Yumm for a one-off Feywild realm or something. Maybe even part of a Dream Plane. Anyway, I guess we'll have to wait to tuck into Yumm until sometime in some other campaign!