Hopefully a few other SanDisk users will provide direct answers to your questions?
Have you determined whether using other tags in the metadata beyond Album and Title will affect the database size?
-> I do not know the answer. But I suspect the Sport & Jam simply ignore many of the metadata fields in the ID3 tag.
I read on this forum that these devices prefer ID3v.2.3 ISO-8859-1. I looked and all the audiobooks my wife has are v.2.3 UTF-16. Do know if that can create issues?
-> I do not know the answer. But I have learned alot from a few rounds of trial & error to achieve functional results.
Since you are asking about ID3 tag metadata for the Clip Jam, I recommend using the software “mp3tag”.
This software has a amazing variety of “macro” commands that can apply specific, desired changes with the click of one button.