I couldn't resist getting the game @ 92% off.

I may try vanilla mode to get the basics of playing it.

I just love mods like the Star Trek / Star Wars mods for games and similar mods.

Thanks in advance...

I went to the Nexus mod home page and downloaded and installed Vortex, their mod manager.
Then I search and selected which mods I wanted from their site catalogue relative to Xcom 2 (vanilla, no dlc) and thanks to Vortex integrated functionalities, I downloaded and deployed them.

To activate a mod there is still a final "manual operation" you have to do by yourself:
Open the game installation folder, go inside XComGame folder, then inside Config folder.
Here, open the file DefaultModOptions.ini with a text editor, and add a line for each mod you want to activate (each mod you deployed with Vortex).

I'm currently playing with these mods:
ActiveMods="FreeCameraRotation"
ActiveMods="ShowHealthValues"
ActiveMods="FlankPreview"
ActiveMods="CostBasedAbilityColors"
ActiveMods="ShowMeTheSkills"
ActiveMods="FreeReload"
ActiveMods="MissionTimeRemaining"
ActiveMods="EvacAll"
ActiveMods="ImmersiveNames"
ActiveMods="NicknamesExtended"
ActiveMods="LW_SMGPack"
ActiveMods="CapnbubsAccessoriesPack"
ActiveMods="StopWastingMyTime"
ActiveMods="Non-snappingGrenades"
ActiveMods="SquadCohesion"
ActiveMods="LifetimeStats"
ActiveMods="MissionAwardVariety"
ActiveMods="UpgradeReminder"
ActiveMods="TechTree"
ActiveMods="More Nations Mod"
ActiveMods="Militarycamos"
ActiveMods="IIIGrimStyleArmorIII"
ActiveMods="XComInternationalVoicesPack"
ActiveMods="Combine'sLoreFriendlyCharacterPool"
ActiveMods="MoreRandomBackgrounds"

The ones in bold font are just Quality of Life enhacements that I find essentials to play the game.

Your are welcome.

Please note I gave you bad information here, when I wrote:
"To activate a mod there is still a final "manual operation" you have to do by yourself:
Open the game installation folder, go inside XComGame folder, then inside Config folder.
Here, open the file DefaultModOptions.ini with a text editor, and add a line for each mod you want to activate (each mod you deployed with Vortex)."

This manual part is not needed, in Vortex there is an automated feature that does that for you.
In the interface there are two sections you will use to manage the mods, "Mods" and "Load order".

When I wrote the first post I was only using the "Mods" part.
In "Mods" you will see a list of all the modes (you have added in Vortex) for the given active game (Xcom 2, of course) and you can manage each single mod (Install, after a download, then Enable or Disable).

In the "Load order" part, you will see a list of the Enabled (and only Enabled) mods for the active game.
Here, you can manage the load order of the mods by reordering the list with drag-and-drop.
Only the check marked items in this list will be injected automatically in the DeafultModOptions.ini by Vortex, and in the order they appear on the list. These items are not check marked by default (So I was missing this part, hence the need to add them manually in the file).

This is so much more convenient to manage mods.

Only disavantage of Vortex/Nexus mods site is that there are some mods not available there.
Steam Workshop is the other source of mods, so if you need a mod that is only present on Steam Workshop and you cannot access/subscribe the mod on Steam, you can use this service:
https://steamworkshopdownloader.io/

Thanks to Vortex functionalities to deploy/enable mods and the above service to get the mods not present in the Nexus site, I finally managed to set the game exactley as I whished: (the bold ones are mods I could only get from Steam Workshop).

If you are intrested to some Star Wars mods, I think you will find something (in the Steam Workshop for sure).
No total conversions, but mods that customize the Soldiers looks and voice packs.

Have fun!

P.S.: Also, if you have any questions or curiosity about one or more mods in my list, or about the use of Vortex, feel free to ask.