There's a mod for both modern XCOM games that's actually just straight-up better than both modern XCOM games. It's called The Long War and was made by the people at Pavonis Interactive, and they've been making their own alien invasion game since forming a company in 2015. We first got a look at Terra Invicta last year in a brief trailer, and since then it has moved forward into development with gusto, culminating in a successful Kickstarter campaign this past month raised $216K.
In Terra Invicta, players will coordinate the Earth's strategic defense while playing as one of several different competing human factions promoting their own ideologies. That plays out like a grand strategy or 4X game as the player sends armies to confront horrible alien Kaiju and secure crashed spaceships.
While defending Earth they'll also move into the solar system at large, mining space resources, developing industries, establishing colonies, and establishing space defenses. Those ships are controlled in pausable real-time combat with the player "commanding maneuver and fire control for Earth’s warships."
Terra Invicta is scheduled for a closed beta in March of next year before releasing in Summer, hopefully August, of 2021. You can find Terra Invicta on Steam.