I started a bullet journal over a week ago. It's not for planning, but in practice a diary with one liner explanations of mostly "important" stuff done, including game project entries for each time I'm working on them. I can't plan for the future, but bujo is making decisions easier to do, because each of them is a branch that takes you closer to some goal, or not.
It has already revealed that my life is quite boring. I knew that, but when you look at the entries back in time it strangely becomes more tangible. The way you can "plan" is change things, create new type of entries with activity that is somehow different than before. It's also forcing me to do at least something each day, rather than fall into my default mode which is watching youtube videos.
I think this is really nice tool for roguelike developers for sure, and it's something I wish I had figured out much earlier. Like most of the things anyway. I guess you can write journal to a text file, but my bullet journal is an actual physical notebook.