Just stumbled onto this Mac/iOS app. A mindmapper with colored tags, dates (and Smart Lists based on date), and it can be used and viewed either in task/outline view or mindmap view. Free trial download, and only a one-time $9.99 to unlock (not sure if the iOS app also requires a separate $9.99 - still, cheap!)

https://eyen.fr/

Aside from the node-header there's a small Notes section, but the screenshots don't show what large amounts of text look like in that field, or how much is displayed in mindmap mode. Interesting though.

Screenshots:

https://eyen.fr/images/en/screenshots/screenshot3@2x.png
https://eyen.fr/images/en/screenshots/screenshot4@2x.png

iOS app is iPad only?

Yes, it's apparently brand spanking new there.

https://youtu.be/PNIa3mzT8Iw

Looks very interesting. The developer says on his Twitter feed that the iPhone version will follow shortly after the iPad one.

It is a rather nice app - I’ve tried it out for projects. But there are certain irritations; the behaviour of the mind map is odd and sometimes unpredictable. However, this was quite a few months ago. It might have improved since then.

It hasn’t been good enough to topple NotePlan…

TaskHeat for macOS is available through the SetApp subscription, too. I've tried it a few times over several months and it never seemed to grab me. I think because I prefer outlines for this sort of thing. But is looks pretty.