I guess that's the really great thing about ESO, if you like both worlds. I for one didn't like the shallow quests of WoW, and people claimed that that MMO was revolutionary in its quests and lore compared to previous games—because there were actually quests and storylines!
Well, WoW was something of a revolution - because it was the first MMO to have PvE progression center almost entirely around story-driven quests.
I agree that the quests were mostly shallow, but in the beginning of WoW - there were quite a few elaborate ones with interesting chains. I was always particularly fond of the Duskwood questline, which was a pretty serious gothic Ravenloft kind of story.
As WoW has "evolved", however, I find the quests entirely forgettable. Not because there's no story involved, but because it's so inconsistent and the vast majority of them are silly and exclusively for kicks. There's no incentive to engage myself in the lore at all.
That's very unfortunate, because I think WoW has the most compelling world of all the MMOs - and it has a tremendous amount of visual variety.
That's one area where ESO disappointed me, because even though it's quite vast - there's a distinct lack of visual variety. Now, I'm not saying there's no variety - just way too little of it.
For instance, if you take the Aldmeri Dominion areas, it's essentially all forest with limited visual variety - as in shades of green. I like the capital city tree, but that's about it for standout areas. That gets old really fast, for me. That said, I guess it's true to the lore of the Bosmers, but that doesn't help much.
I've played all three factions, but I've yet to see the swamp areas of Ebonheart pact - and I'm hoping those might stand out more.
Craglorn is pretty cool, though, as it doesn't really resemble the other areas.
But you're right, the quests are very good - as is the writing. The voice acting is mostly decent - though there are awkward examples in between.
The most impressive part of it is the sheer amount of quests and how elaborate they are. It's probably the first MMO to offer literally hundreds of hours of completely unique quests.
Other games have made that claim, but the truth is that they end up offering a mixture of unique content mixed with mostly repetition of one kind or another. SWtoR is a good example, because they seriously claimed the game was like 12 KotORs all in one. That's a laugh, because if you take the combined hours of unique class quests, I doubt they add up to much more than 30 hours when you take away the travelling. The rest are sidequests that are identical for each class on that particular side.
I'd say ESO has around 3 times the amount of combined story content - and it does NOT bog down the player with endless filler combat and pointless walking around.
That's pretty damned impressive.