Playing with the idea of using Matala as both a false bottom and a (hopefully very well draining) support structure for the background. I'm very happy with it as a false bottom and my initial impression as a background is positive as well. It does take up a fair amount of floor space, but I think if I work the planters, ghostwood, and cork into it a bit before adding any foam I can make up for that while maintaining the structural and drainage benefits.
I'll obviously use silicone/foam to hold it into place, but I almost don't even need to. (I'll also be covering the bottom piece with a substrate barrier and cutting a small piece out to allow for installation of a drainage bulkhead.)
Probably no more progress until Tuesday at the earliest, but hoping for a big update by the end of the week.
If you have any suggestions or critiques, I more than open to them. (I can't promise I'll change anything, but I promise I'll listen.
(Very) Preliminary Layout