I'm afraid it is too late for this but...I think it would be cool if we would be able to change the game-world totally with our choices. This is probably impossible for the main quest but I want to be able to do whatever I want about quests. I guess you remember the mages guild and fighters guild quests of oblivion :
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What if we wanted to help Blackwood company or necromancers? Such as: "After beating fighters, all fighters guild halls become blackwood company halls... And everyone is talking about their immoral actions, innocent people being killed...etc."
Why can't I help the other side? You remember Dar-Ma?
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Don't get me wrong I am not a bad guy and all my characters are good guys, however, I want to have the freedom to choose whatever I want for every quest. What do you think? What if we were able to take money from the people who kidnapped her and tell her mother we couldn't find her?