Re: XL extra tall Exo-Terra build
Corydoras catfish are social. If you don't have the room for a shoal, get rid of the one.
Careful with that Nepenthes. They're great, but they can grow fairly large. Make sure its pitchers never get large enough that a frog could fit through the rim. If it starts getting too large, you can acclimate it to live as a houseplant, that's one of the hardier neps. I have one that grows happily as a houseplant over a saucer with some water in it for humidity.