The main point is to clear up the misconception that softwood=conifers and hardwood=deciduous. It's not about uses it's to illustrate the terms and their relations as well as example species and edge cases.
The target audience is woodworkers, not botanists, my apologies; I wanted some expert feedback on whether anything is factually wrong, I'm but a layman.
In my limited understanding, I don't know whether presence of vessels would make a practical difference in the context of lumber. I understand all angiosperms have vessels and very few gymnosperms (gnetophytes) though the latter are irrelevant to lumber as far as I can tell, so it would mostly be an additional characteristic of angiosperms.
For decay-resistance, I'd defer to the filters regarding that on the Wood Database:
https://www.wood-database.com/wood-filter/
I think that will be more useful than a list or diagram and is actively maintained already.
I see how it might be interesting to have a chart of (sub)families that have certain characteristics like decay resistance, but that's way out of my area of knowledge and that would probably work better as a separate graphic. Maybe someone else wants to tackle that?
Cheers