Thinking it might be useful for people to add their own custom category(/ies)…? I don’t think you’d want users to add more than a couple, otherwise it could get a bit messy. See below screenshot.
Users would need to add purchases to their category(ies) manually but / and over time Curve could learn which kind of purchases to put in there (e.g. all the ones from a particular store).
My use case is the category ‘DIY’ as I’m doing up my flat (yawn!). Loads of trips to Toolstation, yay.