there are mods that fix and even remove journal entries after a quest is completed, there's even a mod that stops quests forced upon you and allows you a dialog to refuse the quest when forced upon you, like the dawnguard quest The Choice is Yours - Fewer Forced Quests - Improved Dialogue Options and Quest Eraser -- Remove Quest Objectives from Your Journal the quest eraser mod I have installed but unsure if it's working, all's I know is that the get certain side quests from the dawngaurd are no longer in journal after a while after getting all the essential rewards and weapons etc!..