Think many MMOs have done a far better job at immersion when it comes to storyline. You have neat phasing like technology in ESO, and solo questing barriers in place, yet so many quests are left open to the public which just doesn't make sense. In most MMOs now important story aspects are instanced off to not ruin immersion, SWTOR, GW2, FFXIV, TSW, and on and on. Most MMOs feel like they realized what they are making and make allowances for the world aspect, while ESO so much of the game feels like a SP game instead. It's very odd design when there are bunch of ESO quests that do instance off and are solo player only for storyline reasons, yet then they keep others open. I'm only 16 so far, and have yet to see any reason why this is a MP game other than to kill my immersion.
I can see your complaint about others diverging into your main storyline questing...but I feel you and I are talking about two different things. There are very few main storyline quests. One every five levels, or so it seems. I can't recall mine being interrupted by other players wandering around as I'm fairly sure they were instanced, but I may be wrong on that.
The other quests definitely vary from folks interceding within them, but (again) that is something that is common to MMOs. Just because WoW eventually developed the technology to prevent that, it was still that way for years. SWTOR put you in your own little isolation chambers - I don't know why anyone would prefer that. Either way, it's a hard argument to convince people who have played each that the non-mainline quests in any of those games are as good as the ones in ESO. These quests are involved and brilliant insofar as tacked on sidequests go. You really feel like they matter. Some dude named Master Blaster killing the level 13 bandit prince and getting me a free quest completion doesn't bother me in the least.
Certainly, your concerns on this topic and mine are entirely different. I could care less. I don't play any MMO for the story, it's just a nice side effect. You see no reason for it to be multiplayer other than to kill your immersion when you are level 16 and haven't PVPed, done a dungeon, grouped to do quests, etc? MMOs are about the community. Of course you won't see the need if you don't involve yourself.
I never felt SWTOR was being another KOTOR, it was another theme park WoW like clone, that was clear from the start. So much of the hype though here has been how this game feels like a true ES title, yet having played most of the titles, I'm not seeing it at all. As you say, you give up to get, but what am I getting as I have yet to experience anything other than a substandard ES offering that has a sub fee? So I'm losing a ton of the freedom and options of a standard ES title in favor of what exactly? It does just feel like a step backwards, a limited version of a ES title. I still have to try the pvp to see if that gives me a proper framework but right now it's hard, but alas my money is spent so I might as well try and see if my opinion changes. I would like to experience a more lived in world when it comes to a MMO, stuff like FFXIV recently did a good job of it feeling like a busy living world because of the players in it.
My point was that SWTOR detractors whined that it wasn't KOTOR (though there were a good deal claiming it was a WoW clone, as well). You are more or less doing the same thing for this new MMO, which I find amusing considering you are a longtime SWTOR player. ESO isn't a traditional ES game is what your complaint is, is it not? What freedom are you losing? What specific features are missing from this massively multiplayer version are the ones you cannot live without? I can't speak on that in depth because I never got too into the console versions of the game. The emptiness never appealed and I detest first person perspective with a passion.
As for a busy lived in world...your primary complaint is about how folks are running around interrupting your questing like crazy, so how can you say the world is not busy? I see players everywhere. There are very few questlines I've done where I haven't encountered at least 3 or 4 others (and often more) doing the same thing. Towns are littered with NPCs and other players. I find it amazing, honestly, coming from a game like SWTOR which definitely seemed empty in a lot of places (Corridor-scant for example). FFXIV is a good example, I'll give you that, but this MMO seems quite busy and lifelike to me particularly in comparison to a game like SWTOR or TERA or Rift. Even compared to Wildstar beta, really. Basically, right now it's busier than any game that isn't WoW when an expansion hit. It's definitely busier right now than the last few times I logged into FFXIV.
I've hit 10 and 25 in EP, 10 in AD, and two 6's in DC factions and they all seem well populated. They should, though. It is launch. I don't understand what you are meaning by this.
I am still interested mainly in Wildstar. The combat is solid with just need of tweaks. My main issue with the game is the lower level content questing, but once you get high enough level the game really opens with that robust housing and the game has some very nice features that still have me interested in doing. Their pax presentations really impressed me with how they plan on keeping the content fresh.
On the Wildstar front, I was referencing your disappointment in how it was yet another WoW-like clone that didn't change the game like you wanted. I'm not sold on the combat style either (for PVP at least). The story isn't much to write home about, as well, and is certainly more deserving of complaint than ESO's. All that said, I will definitely be trying it out. I try 'em all out cause I'm a sucker.
You said your main issue with Wildstar is lower level questing...which appears to be your concern here to a degree when you get down to it. Maybe you are okay with MMOs, it's just that don't like leveling to get to the good stuff?