I'm right before the end sequence; gathered all of the allies for Bruma. I don't know what's stopping me, but I'm at the end of the KOTN quest too, where I retrieve the sword. I'm not sure if I should just finish out the two, and then qork on the mage guild quests and SI. I kept the Main Quest open because I wanted to get all of the sigil stones I needed before I closed all the gates.

I hear that SI and Dark Brotherhood are probably the best storylines, so I'm saving them for last. I just feel like I'm stalling, and just want to make sure that there really is no reason to finish both of these, and move on. This game has been so awesome ( I have 25 games not yet played because of my OCD with this game), I'm afraid of missing out on any little thing.

http://www.uesp.net/wiki/Oblivion:100%25_Completion

If you're not quite that bad, then there's no reason not to finish out the MQ. Honestly, I tend to start and finish it early, just to get it out of the way. It's one of the more tedious aspects of the game, frankly. Various user-made quest mods, as well as some of the pre-existing quest chains (Thieves Guild, DB, SI are all good examples) are substantially better, and if you like immersion there's absolutely nothing wrong with just installing a bunch of visual mods and going exploring.

Totally obsessive-compulsive about this game. I'm getting similar feedback from other forums too. Thanks.