Some good points Mike
I don’t know how Webflow plans their projects but I can imagine that the style panel is a different team than most of the points on your list. I am not taking sides here. Just airing own thoughts.
I think this is rather difficult to do (again I don’t know exactly how Webflow operates) if they are using a static site builder. They normally rebuild all when you publish. Even they could rebuild partially then they would need a lot of logic in order to make sure they republish the pages affected by the change. Like links to that page, snippet of content from that page. Perhaps a complete rebuild is fine with you as long as your other changes are not published though. You mentioned partially finished changes. Perhaps Webflow could introduce a queue system where you can push certain changes in front of the queue and only then publish 1 item in the queue only.
Does CDN not work with HTTPS sites? I am very curious about this