User blog comment:Magma-Man/Merry Christmas!/@comment-4733316-20111229011440/@comment-1956117-20111231015240

I'm not sure about some of those examples, but yeah, you don't have to exactly go by the main quest once you're well developed into the game. For example, I'm currently working with the Thieves Guild instead of doing the main quest (well, in one of my profiles lol).