What feature do you want to see added?

What if you are at y > 64 and the depth d is locked at 64 to look for the block (actual behaviour at the moment)?
Minecraft has a different y value since 1.17.1 as far as I remember. Heighest block is Y=320, lowest is -64 in the overworld, heighest is Y=256 for the nether or the end. d should limit at the lowest and heighest value of the world I guess.

Are there any alternatives?

You might have to dig down to find something but that might take a while or you use fawe to find a block.

Anything else?

No response