Same situation here. For heavier editing I now use local Stirling PDF and BentoPDF. As I say above, both run in docker, but Stirling PDF also comes as Appimage. They are powerful but don't feel like integrated applications.
But there is a surprising gap in Linux for PDF editing. Available tools are like toys for the task or geared towards techies. I would expect a PDF reader/editor to be a separate application in the LibreOffice suite. (No, Draw or Inkscape won't cut it, sorry)