Substrate options?

[MlizGr]

Alright, so since my lovely little Achilles Heel [yellow bellied Racer] was a surprise snake I've been using paper towels on the bottom of the cage for a "substrate" of sorts. He seems to like to hide himself right under the edge of them, so I'm thinking that I want to figure out something he can burrow through [once he's healed up from his cat attack first! All his wounds were looking great today though, and he's definitely on the upswing!]

So, what are some of the more natural looking options for substrate? I've considered doing a planted tank to be rather... prairie-ish? I've got some antlers in there for him to climb on and for decoration, along with a cool twisty stick I found and baked some time back. Even his water bowl looks rather naturalish [though I am considering getting him a larger one so he can soak easier...]

I've already read that sand isn't a good choice, so that's out. In terms of plants I was thinking some of the spider plants I inherited and are starting to take over the house. Would I keep them in their own pots or would I be able to plant them into some kind of substrate?

And yes, I'll get photos of the tank so far and put them up as soon as I get home, and there will be more photos of Achilles as well!