If you are looking to play sandbox, without the main quest, just ignore it. Thats what I am currently doing. I'll admit I've talked to the lords and gathered all the pieces, but I refuse to talk to Istiana or Azragos to put them together. There's literally no benefit to it. You don't get lords flocking to your banner. You don't bonuses to tax collection because people love you. If you give the banner to another lord they say its the best thing anyone has ever done for them, but it doesn't even improve relations with them. No benefit at all. In addition the quest penalizes you by having a conspiracy that, as far as I'm aware you can't stop, give you overwhelming foes all at once. The only thing you could point to as a benefit is that you get start your own kingdom at clan level 3 instead of 4. But I look at that more as a penalty for not doing the quest than a benefit from doing it. If you have the ability to start your kingdom at level 3 and the game stops you because you didn't do a quest you are being penalized, not rewarded for doing it. Anyways, so I'm not doing the quest this round. So far its not going badly.