Some thoughts for folks getting back into the game:
Moria is still my favorite part of the game, and it has been made easier to travel around and easier to solo since release. Most of the original game has likewise been updated along those lines.
I liked the Isengard expansion, but it feels like it starts slowly especially if you do all of Enedwaith first. Dunland and Enedwaith have a samey-samey sort of feel to them, I think. But I liked Isengard and the Grey Company stuff well enough.
The Rohan expansion is a problem though, and I gather this one marked the decline of LotRO. I don’t think it is paced well and the story kind of peters off without a significant end-game, one that I found easy to just miss entirely. Which is less of a problem now that you can just move on, I guess. But you can’t avoid mounted combat. Which is occasionally fun in some instanced quests but otherwise… not so much. It starts off badly because you need to level up some horse attributes just to make it seem like you aren’t driving a tug-boat, and the combat itself isn’t particularly interesting what with the limitations of the game engine. Oh well - you can power through it and mounted combat becomes more or less optional in later expansions.
Helm’s Deep is also fun I think, though. Although most of the expansion is actually just getting there. Many people seem to have shrugged off the end-game Epic Battles… which might be fair. Like mounted combat you need to level up some stuff for them to be interesting, which means sucking at it for a while which isn’t exactly a good introduction to a new mechanic. They’ve grown on me though, and I do reasonably well at them now. They seem at first like a pointless iteration on the Skirmish system, but they are fairly different, I find.
After Helm’s Deep you get into Gondor and the new release cycle where it is just a zone at a time every six months or so. People seem okay with this versus the big expansions, and since the server merging things in Middle-Earth seem active again, now, out there. I’ve liked a lot of what they’ve done in these expansions (particularly fond of Dol Amroth and Osgiliath), but I lost interest in the middle of Minas Tirith (but they’ve overhauled the travel system - again with this! - so your experience might be improved) before I got to the new Epic Battles. And the newest expansion - Battle of Pelennor Fields - does have some fairly good bits, but I’m getting this suspicion that I’m paying more for these last two expansions then I’m getting out of them.
Some tips: level 100 legendary items can use an optional alternate leveling system that seems to more or less fulfill the promise of what legendary items were supposed to be when they were introduced like, ten years ago. I would entertain skipping using legendary items until level 100 if I were going around again, maybe only just keeping some items in the slots, leveling them up, and deconstructing them for item experience so as to have a pool of it available for later.
It’s also good to keep in mind that there’s a lot of scaled level instance and skirmish content to fool around in. I’m doing the Osgiliath instances at level 50 - no noteworthy reward other than finishing up some quests and seeing some new content, but that can be enough enjoyment by itself, I find. (Also, I’m too lazy to join groups.)