Complementary shader just got an experimental update to v4.0 that includes (some) compatibility with the 1.17 Optifine preview.
This update makes Complementary behave pretty well with the new 1.17 features. It supports heights/depths below Y=0.
If you want to know more about the Complementary Shader by EminGT you can check out his Discord server, or get the latest releases of the shader on his CurseForge page.
I wanted to do a couple more screenshots while exploring the new caves worldgen, and boy the caves are GINORMONGOUS. I got lost flying all around, deeper and deeper still. I haven’t discovered much besides the deepslate caves but it looks absolutely stunning.
Here are some screenshots with Complementary v4.0 dev and Vanillaccurate v1.8.0:
Copper in stone 
Not a 1.17 block per se, but I wanted to showcase the new Redstone with the 1.17 pattern 
Same here with the new coal ore pattern 
Coal ore again 
Deepslate 
Deepslate with gold ore
More to come soon, I just barely scratched the surface (pun not intended) and I’ll design more 1.17 blocks after the v1.8.0 is live.
HardTop Vanillaccurate 