You can save a lot of time by using axesPDF, the professional checking and remediation tool for accessible PDFs.
Download the current version here:
axesPDF Download Page
Full-featured Trial Mode
You can explore all the accessibility checking and evaluation features in this version without activating the software. Use axesPDF as an advanced PDF/UA checker and for in-depth PDF accessibility evaluations. The only restriction is that you can't save the changes you make to the PDF document.
So download the trial version, check it out, and let us know what you think.