I used a crap ton, I'll try to give you the essentials.
Hair & Face
Colors
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Hair
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Face & Makeup
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Steam Workshop :: [WOTC] Sudden Attack 2 Wetsuit (Includes the face I used on all of my Asian soldiers)
Steam Workshop :: Ketaros Makeups Package (Makeup, will not work with the first link of this section)
Clothing, etc
Steam Community :: ($S360)Aeronautic :: Workshop Items (Basically everything this guy has made that interests you. For me his 2B outfit mod is a really important commodity because I've used it for like 90% of the zako in my previous post (like the only thing that has big thighs and high heels) but it's kind of finicky because it doesn't mesh well with other torsos. I find it's easy to hide the seam with the belts provided in the SA2 wet suit mod or the SA2 Miya Customization Pack (listed below)).
Steam Workshop :: [WOTC] SA2 Miya Customization Pack (Contains belt and hair I use a lot)
Steam Community :: Astery :: Workshop Items (probably fair to install almost anything this guy has made as well).
Steam Workshop :: WOTC Female Clothing Pack (adds a ton of options).
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[XCOM 2] Mod index (There's some lewd stuff on Loverslab if you're into that)
Lewd mods and XCOM 2 (Or use this thread if you'd like to do some digging, but try to make sure you're downloading the most recent content (WotC)).
Things You Should Probably Install for Gameplay/Compatability Reasons
I'm just including mods that'll make your experience less painful, these shouldn't impact gameplay or difficulty. I've also put in stuff you might need for the previous character creation mods to work. I'm not sure what the mods require so I'm sending the content I'm subscribed to, just double check when installing to see if the mods require anything.
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Do keep in mind most of the mods I've listed and all of the mods that will probably come out for this game are for the latest WotC expansion and likely won't work with the default game (WotC is basically the same thing as the default campaign with a bunch of new stuff added). If you don't have WotC most of this content isn't likely to work. Also, there's a veritable fuck ton of voice packs and other customization options on the steam workshop that are worth checking out if you're not satisfied with everything here. Let me know if there's content you see in my pictures that is missing in this post.