So I'm looking to do everything the game has to offer. I have the Legendary Edition and even picked up the hard back of the Legendary Edition guide but I feel like I may miss something. My main worry is I might kill someone or do something that causes someone to die or something and not be able to do what I could have for them. Example: When you start doing the civil war portion of the game lots of people die and some are farmers that I could have sold crops to or what not. That is the kind of thing I'm talking about. Any help would be greatly appreciated. On another note, If there is anything that you come across in Skyrim that you think some may have overlooked or don't know about or that the guide doesn't focus on "it misses a lot of the fine detail stuff!" then post it as well. Thanks in advance!

Really important People are protected by Essential Tags, and only one Farmer from Whiterun dies during the Civil War. Going around like many Players as a Homicidal Maniac is not a good idea at all.

The UESP is an excellent source on specific problems with many Quests. Bookmark it and use it, especially if You enjoy being Criminal Scum. The Dark Brotherhood and Thieves Guild can eliminate some Quests from the Game.

Do not try to do Everything with just One character, it takes some of the fun out of the Game.

I do not have the Prima Guidebook for the Legendary Edition, but the Guide for the Vanilla Game listed content that was removed from the Game prior to being shipped to the Public, like finding missing Mage Apprentices.