I use flows as a way of storing ideas and it works well.
Using a single flow for all ideas isn’t really an option for me - I’ve tried it many times - since a favourite scrap can quickly get lost with proliferation (especially in larger scores). Individual flows for separate ideas is my preferred way.
There’s often little clue from the title of a flow what the contents are, especially with a connected series of flows each containing a different, maybe fully worked out version, of essentially the same passage. So, some system of organisation (grouping of flows) would seem appropriate with, maybe, a snapshot of each flow (as in the Ideas panel referred to above, or a mouse-over pop-up window).
Having said that, I bless the day Dorico and its flows came along. I’ve said it before and I’ll say it again: thanks for flows.