Hi David,
Great question. So with regards to upgrading your wordpress installation I would definitely upgrade to the newest version for security reasons. The main thing I would do is make sure all your installed plugins support the new wordpress version before upgrading.
Also if you can or have softaculous or another backups solution I would do a full backup before doing the upgrade that way you have the ability to go back to the old version install and or your working install.
Wordpress has since added the new gutenberg editor to the platform and that can be nice to have depending on if you don't already have a builder.
Let me know of any questions!
Mario Cano