Just a quick 3 ideas:
1. What if it was darker (as to simulate being underground), maybe visual holes to the surface that light up the caves, like in the greener caves.
2. Using explosives when placing rockects to simulate breaking a hole to the surface?
3. The random clusters of trees gaining a more root-like look to make it more believable its underground.

Feel free to ignore these if you want, just thought they were decent ideas : )

Thanks for the feedback!

I like the idea of pushing the underground atmosphere further.

Darkness and surface openings are definitely interesting ideas, although I want to be careful not to make visibility frustrating for players.

The Cave started as a simpler fork focused on removing collapse mechanics while keeping the original Diggy gameplay intact, but I'll keep your suggestions in mind for future updates.

Thanks for trying the mod!