Well you can consolidate the two saves and you should definitely! there may be a point when they both try to save at the same time and it will corrupt data. And yeah it is tedious but EVERY game engine is like that.
In fact any piece of code is like that. While programming, you have to account for EVERY bit of data and address it by each variable. There’s no way around that. Once the concept settles in, it’s really not a headache, I promise. You get used to it and expect it eventually.
But long story short, yes. You need to save every variable that you want to load. It’s like making a sandwich. Most people would say:
first you get the bread, then you get the peanut butter, then then knife and then you spread it and eat it. In programming it’s more like: First you flex your arm, then you raise it, then you move your fingers, then you move your arm, then you touch the jar, then you grab the jar, then you lift the jar, etc. etc.