Good summary, hit most everything. Only thing you missed that I'd say warrants pointing out is the change to skill mastery books.
Here's a section of a comment I wrote on reddit about a year ago with regards to someone who was coming back after a long hiatus, much like yourself, OP:
(Edit: the price was changed sometime in the past year. The price was reduced by 2m for each book. 5m -> 3m; 7m -> 5m)
To a brand-new player, the cost does sound fairly expensive and, assuming you haven't made an alright amount of money by the time you need them, you'd be right. There are several theme dungeons that give a set(1x 20, 1x 30) of books upon completion as well as typically being available via event shops(like the current glory coin shop for example). It sounds significantly less expensive when I tell you that I once sold a MW20 book for about 120m way back when. That's one 70% chance to increase the max level of a single skill for around 3x the cost of raising all of your 4th-job skills to max level with no chance of failure.
You will be very lost. There is essentially nothing that is the same as when you lasted played, other than the names of towns and continents and some npcs. If I were you, I would treat it as an entirely new game that you're just starting out on for the first time, and not one that you're coming back to after years and years.
Any character with a sealed item cannot be deleted, for one.
Aside from that, it seems more like it would be geared towards people who share accounts so I'm not sure why it exists tbh.
It keeps you from accidentally selling things too. Especially useful if you're the type to have a set of damage and drop gear.
