When my game project gets too big I plan it in a "mindmap" instead of text documents. It maps better to how humans think and how complex projects work - things are connected in many ways and not separated in categories as in spreadsheets and lists. I can see the whole project in ONE image, which is easier to process than a long text, which gives much less administration job which is crucial to even finish it at all.
It's in Swedish, unfortunately... But this is how I can see the project as a whole, its separate details and tasks, how everything is connected, and in some way understand where I am, the next thing to do, and where I'm going.
Here's my current project mindmap: https://notacarclub.kbrecordzz.com/WIP/mindmap.png
It's in Swedish, unfortunately... But this is how I can see the project as a whole, its separate details and tasks, how everything is connected, and in some way understand where I am, the next thing to do, and where I'm going.