Kiritsugu's ideology is very interesting. He believes everyone is equal, hence sacrificing a few to save many is morally just. And as utilitarianism is a theory born out of logic, it is very hard to argument against. However, this brings him a lot of pain and shows humans simply can't live like this, we aren't machines. We prioritize our loved ones over random people, we see death as a bad thing no matter the circumstances. Eventually he'll abandon his ideals and save a kid from the catastrophe and raise him.
I adore how it uses myths and history as inspiration for characters. Reading into why they have certain abilities is always fun.
The scene where Artoria, Iskandar and Gilgamesh sat down to talk and drink vine was great. Arthur believes a king exists to serve its people, Alexander thinks king's purpose is to expand his empire and Gilgamesh (he represents the ruthless king from the epic of gilgamesh before he met Enkidu) says the kingdom's purpose is to please its ruler.
