I think your suggestions are well worth trying. I don't want to build the second-brain or knowledge graph that is so often discussed here -- as a secondary effect, I'd be happy if that happened.

But I also know there are two kinds of ideation I want to capture better: lightning in a bottle thoughts (the idea I had for my son came to me while we were bombing down a ski bowl), and thoughts that arise during particularly ideation friendly activities -- driving, running, working out, lying in bed, etc. It can be hard to stop the activity to record a lot, but it's stupid not to record at all (as in the story with my son), and sometimes I'll need to record more or at least record more as close in time proximity as I can manage.

I'm loathe to use voice memos, but I might need to start trying it.