There are plenty of articles about open world game design and writing plots. But have you guys come across articles or blog entries about designing an engaging plot in an open world game? What i mean by this? In TES:Morrowind you're introduced to mechanics and are given the "main quest" within the first 5 minutes and then you're free to go, learn, kill, do whatever you want. I've spent hundreds of hours playing the game, but i have never got to doing the "main quest" and i'm sure alot of people are in the same situation, be it Morrowind, Oblivion or Skyrim. Maybe it's the power of TES games and a true testiment to how great RPGs they are, however for me, thinking as a designer, it seems like a massive design failure. Maybe it's the fact that there's no actual threat that needs to be dealt with, maybe it's that, amongs all the well designed and interesting quest within the game, the "main quest" just doesn't seem so interesting.
I've got a game idea in the back of my head, i want to create an action platformer, but the "level selection" would be open world style "dunegons" like you find in MMOs. This is a vague and undeveloped idea, so don't focus on it, i didn't give this design much thought, however an issue arose, i can't figure out, in general, how to make the player care about the open world aspect (f.e. dealing with roaming, pillaging parties, doing a gauntlet run to get some special armor, clearing a water source from enemies, etc.) while "forcing him" to finish the game, carrot-on-a-stick kind of way. There are "crazy" people who will go search everywhere between cutscenes in FF games, but i'm aiming at the general audience. I want to create a subtle system for guiding people throughout the game to a goal, while giving them an option of gaining power any way they want. This may aswell be impossible, but it doesn't hurt to ask.
I'm looking for articles or musings on this matter. Not solutions (since there's no design document, no direct solutions matter at this point), just thoughts from other people, probably with other games as a reference.