When you look back at the best of Marvel, all of those great movies and shows are built around drilling into a deeply flawed character and forcing them to make choices that get right at the heart of who they are. Tony Stark's narcissisism, Steve Roger's martyr complex, Peter Quill's self-blame, Peter Parker's insecurity, now Simon William's isolation. That's the secret sauce to a great superhero show: find the flawed person (because we're all flawed people) and give them no place to run. It's why Tony Stark's final choice is the perfect way for that character to go out, and it's why Simon's final choice in this series hits so hard.
It's a cliche to state that great stories are always human stories, but it's true. All the special effects in the world can't save a story that has no heart. This series is ALL heart. I just adore it.