Wow interesting with all these fonts! For print as image I would say for small fonts to go at 800dpi -1800dpi that would be good. What point size are you using?
If you "print as an image" and output another pdf file instead. Then extract only the problem pages from the orignal PDF and insert the new PDF pages that you've just created. That should temporarly control how the pages are printed by clients eventhough the file maybe now larger.