The Ending
I'm on what I think is my 11th rewatch right now.
I love the show from start to finish. I think my only issue with it as a whole the very very end.
I think there were three possible paths that they could have taken, and they took the worst of them.
Cadogan is incorrect about the whole thing. No higher beings, no transcending. He's still stopped, everyone alive goes back to earth.
Cadogan is correct. They prove humans are worth it and they transcend. (The Canon ending)
Cadogan is also correct here, and things play out the same right up until Raven goes to bargain with the higher entity. Instead of Raven convincing it to let humans transcend, she asks for a reset. Humans are brought back to Earth, the Anomaly Stone is rehidden somewhere else on the planet, and they start from scratch again promising to do better. Predictable flash forward to decades/centuries later, Wonkru has once again dissolved into the clans. The human race is once again at war.
In the end, I think a clean and "satisfying" ending does a real disservice to what the show portrayed for years: that the cycle is impossible to end. Forcibly ending it by having the entire human race transcend, only to tack on that those who choose to stay behind won't be able to have kids? It just leaves a bad taste in my mouth every time.