I've had a lot of trail and error with this as I started my application in Builder 6 and have been steadily porting the source to newer versions of C++ Builder and as of late, I have been having this large PDF issue.

I have managed to get a single page down from 3MB to 200kb and still working on finding the best settings. But this is what I have done.

On frxPDFExport:

Compressed = true

PDFStandard = psPDFA_1a

PDFVersion = pv14