This is the next system on my list which I wish to discuss. A literal example of an "oneshot" system, go, do and never do again. I was leveling earlier via Quests on Return of Reckoning and it was awesome, being on Ulthuan, only for that...! But the quests? Mostly lacking, but I could also say that about SWTOR or TSW and those are anything but lacking. But what happens once you finish playing SWTOR and, say, record everything? You either have an annoying activity or you don't play at all anymore. And if a game focuses on Instances, if a game focuses on RvR...why even include a large amount of quests, why not go for efficiency and quality?
With that said, what type of Quests do you prefer? Just a few main, fully fleshed out quests? A shitton of filler quests so you always have something to do? Something else?