Worlds are generally what people use for this purpose. You don't need to make a World collaborative if you don't want to, they work just fine for solo development—I even have one myself that I use in that fashion. They also have a feature where you can add custom pages (basically, a blank page you can fill with whatever content you want) that seems like it'd be ideal for organizing big chunks of information like you have.
Hallo, I'm new to Toyhouse. Am I missing where you submit species, or is that not a thing? Do you just need to maintain a thread or external page (like a DA journal or w/e) to collect species information or did I just not find that feature? I figured you would collect characters into species and then species into world. No? Help me out. If it's not a thing yet, is it on the devs to-do list?
EDIT: The current solution I'm using is having a character named Infodump at the front of a folder for a setting. I originally thought I should make some Worlds but that seems to be for collaborative work, which isn't quite what I'm up to just yet.