First piece of advice I can give you is to not use the Civil War Overhaul, I've heard there's some issues with it (maybe not supported anymore) hopefully someone else can let you know for sure, but I've stayed away from it, because I've heard of issues with it.
I would definitely use most of Arthmoor's mods like : When Vampires Attack , Run For Your Lives, The Paarthanux Dilema and others.
Also highly recommend Skyrim Immersive Creatures (commonly known as SiC).
Also, High Level Enemies ( since you plan on doing everything in game this playthru, you'll end up getting into high exp lvls)
Also, Elys Community Uncapper (this way you can level skills past 100)
Maybe give a good super follower mod a shot too, such as: Vilja (my absolute favorite, it adds soo much, besides just a follower, but also a very good intuitive follower), or Inigo, or Arissa
After you get thru the Bethesda DLC's , some new worldspace mods. I highly recommend Helgen Reborn , Falskaar, Wyrmstooth, and Moonpath to Elsweyr.
If you aren't using an ENB, and have a half decent PC... Realistic Water TWO , and SMIM (static mesh improvement mod), and Better Dynamic Snow.
Achieve That ! ---adds achievements & rewards into Skyrim
Interesting NPC's !!!!!!!!! <-- very very topnotch mod that adds ALOTTTTT to the game.
Inconsequential NPC's <--- just adds more people to the game, making areas seem more 'alive'
Sounds of Skyrim and Climates of Tamriel mods, those add a lot of ambience to the game.
And of course the most important mods: SKSE, Skyui, all the relavent unofficial patches, and of course use LOOT (it has pretty much replaced BOSS, and is VERY good and the 'goto' load order doodad ).