Post making contest 5.0

Civ victories:

Diplomatic: Kill a few civs to lower the delegate limit
Cultural: Kill the few civs that are producing more culture than your tourism
Spaceship: Kill the civ that's ahead of you in science and is almost done with their spaceship
Conquest: Don't kill the civs, just take their capitals

I am a civ expert and I can verify that all of the above statements are true. But also:

Time: Kill a few civs to kill time.