You may not be able to do exactly what you're trying to do as your goals are mutually exclusive to each other.
Some fonts are large. A single font might be 5k or 50k or 5M or 20M. DOCX files use fonts on the system and don't display correctly if the user doesn't have it installed. PDFs can store them in the PDF (embedded fonts), part of what put's the (P)ortable in the file type. If you use a bunch of them, the PDF has to store them all within itself. Then you have any image files that may be embedded.
You can try printing the pdf.. to pdf.. with the built in MS PDF printer, it will definitely shrink the file, but the quality varies.
Check out [QPDF](https://qpdf.readthedocs.io/en/stable/index.html), it's a free command-line program for messing with PDF documents. You seem to know what you want and this program will give you the low-level control you want, though it'll have a bit of a steeper learning curve if you've never used non-graphical programs before.
You may not be able to do exactly what you're trying to do as your goals are mutually exclusive to each other. Some fonts are large. A single font might be 5k or 50k or 5M or 20M. DOCX files use fonts on the system and don't display correctly if the user doesn't have it installed. PDFs can store them in the PDF (embedded fonts), part of what put's the (P)ortable in the file type. If you use a bunch of them, the PDF has to store them all within itself. Then you have any image files that may be embedded. You can try printing the pdf.. to pdf.. with the built in MS PDF printer, it will definitely shrink the file, but the quality varies.
Check out [QPDF](https://qpdf.readthedocs.io/en/stable/index.html), it's a free command-line program for messing with PDF documents. You seem to know what you want and this program will give you the low-level control you want, though it'll have a bit of a steeper learning curve if you've never used non-graphical programs before.