Exactly what systems do you find interesting and just how exactly is the instancing utilization interesting?
The passage of time and events/character impact on the story/gameworld that is handled via instancing. this combined with NPC draw and placement being handled client side rather than server makes for a more interesting story telling experience than say, SW:TOR, which again, is the other major single player game-made-into-an-mmo that i draw comparisons to.
an example:
bad guys are planning invasion of a town. they are attacking it and burning everything down. Through a series of events you save the day and restore peace, and everyone is saved.
Since the advent of WoW and story/quest based xp progression this generic quest chain plays out in many mmos. since the advent of instances certain segments of this quest chain would play out in (mostly) solo instances. It gives the feel of progression and character impact on the story. The problem when you're heading back to the ? quest giver to get your xp and reward you pass through the same area and watch all the other players dealing with the same mobs from the same bad guys that you just eradicated. It's like a ground hogs day scenario.
Games have tried to alleviate this by having most of the major plot point moments occur in single player "dungeon" instances where major story NPCs can be killed/saved/etc without impacting other players experience (since they are playing the same story quests you are), but the "zone" is the "zone", a common area that all players have access to thus the bad guy army is kinda stuck always spawning in that area always on the "eve of their attack", and the allusion is shattered, your actions have had zero "impact" on the world.
ES heavily utilizes both instancing and client side NPC draw/placement to alleviate this. When I'm throwing water to put out a house fire, busting in and saving all the villagers trapped inside it's happening client side. I'm still interacting with players in a "common zone" area, we can team up to attack the bad guys, i can run in and save him or just tea bag his corpse when he dies, it's still multiplayer, but it's still ES too. My progression through the story, the objects and npcs that i'm interacting with, etc, doesn't hinder him or his progression through the story either. When I reach a major plot point/junction in the story, instead of going off into a single player instance to deal with X only to come back out of said instance into same common area that's still dealing with the threat I just vanquished, I instead move to a new "common instance" in which that threat has been dealt with. The town was saved, the fire's are out. NPCs are in different locations, they have different dialogue. Time has passed, actions have had consequences. Later on in the game when I go back, I don't see players dealing with the same problem I already solved yesterday. I return to a grateful town that was saved by me. NPCs cheer for me when I enter.
LOTR was the first game to use instancing in this way but it was minor transition in a newbie area once (town burned down, when you went back the town was still burned down) and I don't think they utilized it a lot, though i only played that game for a month when it released so I dunno.
The game is still in beta, so yeah there's bugs, half the voice overs are missing still so you get generic TTS on a lot of quests, etc. But the game is getting a lot of hate because people are expecting ES version of WoW much like TOR was a Bioware version of WoW. it isn't trying to be WoW at all. It's trying to be multiplayer ES, which it's doing quite well, incompleteness and bugs aside.
"you run around and press "E" a lot". yeah, ok so basically what you did in skyrim? They aren't starting with a baseline of WoW and adding an ES theme on top of it which is what SW:TOR was. It's starting out as ES and then trying to tackle the problems they see with converting a single player experience in which the player is this prophesized savior/hero/whatever and how to handle converting that into a multiplayer experience. Whereas TOR did it all through single player story instances they've went another direction, and yeah I happen to find it interesting.
None of that is to say that I think this game is the best or worst game ever, or any of that. I just find how they handled the "you are the hero of legend" story based RPG which ES is known for, and converting that into an MMO in which everyone and their dog is "also the hero of legend". Bioware faced a similiar dilemma with TOR and I wasn't a fan in their methods of maintaining the allusion. The game as a game has its gripes and merits, Graphics are fine-ish (FAR superior to FFIX btw, though that's more taste/style I suppose, always hate FF/anime style graphics), controls are just as janky as FFIX (of which i wasn't a fan of). base combat/gameplay is kinda weak, though it's definitely got the ES feel, and ES is certainly not known for it's amazing combat.