There are a couple other interesting things:
Linkshells and Crossworld link shells are invite-only chat channels. One character can be in 8 of each, and you can use this for coordination. I’ve seen similar systems in other MMO’s, but really only FFXI and FFXIV have done it this way, and it’s really nice compared to, say, EverQuest’s custom channels.
In your Inn Room or some player housing / FC housing, there is a device that will let you play most completed cut scenes - and so you can go to it, and play cut scenes to better understand what the heck is going on. This is useful if you skip jobs, but it’s also useful if you just want to see the Hildebrandt quests, for example, and don’t want to level an alt to 50+.
Do you see the sprout next to your name? Congratulations, you’re a new player! There’s a more planty sprout for people that return. Some players who have achieved certain milestones can talk to the Smith that does the new player training, and they’ll receive a crown next to their name. There’s a feature called Novice Network that’s available - but you have to be invited by a crown. The crown might have a sword overlay - indicating a combat mentor. The crown might have a hammer overlay - indicating that person can make pretty much anything you’d ever want crafted. Or the crown might have the white flag of surrender, indicating someone who has killed more than a couple of players in PVP.
Filmstrip by their name means the user is watching a cut-scene. If your healer has a film-strip icon, it is probably not an ideal time to pull a lot of mobs, or to charge that named.
Chair indicates AFK and, again, if someone important has a chair up, you might want to take it easy for a minute or two.
The level sync thing is interesting, but I prefer the way other games have done it where they scale back all the abilities rather than disabling some of the abilities. It is significantly less annoying with Shadowbringers than before, though, for most of the classes I play in that when they did the adjustments to the classes, they typically made upgrade actually use the same button (as many other games do).
As a side note, I really like most of the changes that we see in Destiny 2 versus older as well - one thing that bugged me in Destiny from the get go is that if you were away from the game for any period of time, you would have a significant power gap - and when they put in the expansions (in Destiny 1 and 2) there was usually a gap that required farming to close. That annoyed me significantly, because I’d hop on and want to do something - and wouldn’t be able to see any of the more recent content, because I was a hundred light levels low or something.
This is different from most MMOs where traditionally raids are optional, and so generally the next tier’s commons picks up right after the current tier’s, and then the first quests in the expansion get you the stuff you need to start on the next tier of raids, maybe last tier’s raid stuff gets you mid season, maybe even early end game - but you’re going to replace all your stuff with an expansion.
Destiny just said “meh, you’ve done the raid, you have the high gear.” I was really happy to see them fix that in the Shadowkeep expansion, and also it was nice to see my exotics that I’d hung on to in order to eventually upgrade become usable again.
But it does, literally, just dump you into the story and it’s like “here, have at it!” I liked a bit of the old Destiny 2 storyline better, in that even if you hadn’t played Destiny 1 and had a strong connection to the characters, it tried a little to build that connection. However, I never liked the split home zones and some of the other things that they did, also the incremental changes to looting and upgrades over time have largely been welcome, in my mind anyway.
Have fun, stay safe, and whichever game you play - have some fun.