Why would you do any more work? Use it till you need to clean up or move more. There have been folk that work very hard to move every scrap to the external card and they often get burned as the card fails or an app doesn't work.
I'd stop for now, enjoy the tablet.
I'm using Apps2sd and my tablet is rooted with Magisk. Would there be any downside to converting system apps to user and linking them to an sd card? If it's ok what system apps would be safe to do this? I'm using 8.47 Gb out of 16 Gb.