Speaking about PDF size, AND given that you are working on adding OCR for Image-Only PDFs, I would suggest looking at online2pdf.com.

The really only one, GOOD compression tool with fine-tuning options and which yields the BEST results 100% of time, after years of testing different ones...

(From experience, even as low as Image Quality 3/10 and DPI 120 yields good quality graphics, reducing up to 90% off of uncompressed PDFs).

The developer is a PDF expert (working on it since 2007), nice and, (without doubting your abilities, but knowing PDF is often a pain to deal with) maybe would be happy to help ?!

This would save GB on your servers over time, would allow us to upload bigger files (at least up to the token limit problem), and would really allow to store everything in one place (and being able to download a clean, compressed version of any Card and PDF would be a nice add-on as well !!))