Leaving this for anyone else that might be searching:
After tinkering with Core Data for a while and trying to get it set up, I ended up scrapping Core Data and using the FileManager system. I'm sure there's drawbacks to going this route versus going the Core Data route, but I'm only trying to store two relatively small arrays (less than 50 items for sure, probably less than 10 items in most cases) and a lot of the sorting is done in the app itself. So, it seemed like the easiest solution for now, as I was able to implement it in a few hours using my existing structs.
I used this as my guide, and tweaked slightly for my use case: https://developer.apple.com/tutorials/app-dev-training/persisting-data
While this looked intimidating at first, I found it to be infinitely easier than figuring out Core Data. Just my experience, but wanted to share my experience for anybody who finds this in the future.