help with substrate and cleaning homemade decerations.

[K-Reptiles]

I have a carpet python (not sure what subspecies but not a jungle) and I'm trying to decide between using zoomed snake aspen, cypress mulch or Kritter crumble,
what is the best, for my snake buddy. what are the key differences
from my reading aspen doesn't hold much humidity, but apparently you don't need high humidity for carpet pythons.
really confused, thanks for the help