Thanks for the detailed description of your workflow. It saves my time looking for an unexistent solution.
I stopped using iOS. In macOS my workflow is the same as yours, with the exception that I have the “Open Externally” icon in DT’s toolbar.
But my workflow gets clumsier than yours because I annotate pdfs. I tried MarginNote but, although a good app by itself, I gave it up because of its non-standard pdf system and the additional steps I have to add to my DT-based workflow. I prefer to use the straightforward Annotation Pane.
It is DT’s handling of pdfs that spoils what would be an acceptable workflow. I have to keep searching/going to pages in DT to extract annotations with Annotation Pane of the paragraphs I highlight in PDF Expert -this app has faultless pdf handling, ToC and annotations summary. To make things worse, some pdfs cannot be read by DT.
Apple’s PDFKit has some of the longstanding bugs in macOS (another important one is non-persistent Edit>Substitutions), that I have to circumvent dozens of times a day. It gets annoying enough to make me want to change OS as soon as I can find in Windows a handful of third-party apps my workflow relies on. Hopefully, Microsoft is big enough to solve bugs in its OS! As for Apple’s spectacular hardware, I never valued it as much as my previous IBM Thinkpads -that I used first with Windows and later with Linux.