I like how both the hero and villain of the movie are both incredibly powerful, like powerful beyond belief, and yet they are completely unable to get what they desire the most. Wanda wants her kids and nothing she can ever do will fix that. Strange wants Christine but nothing he can ever do will win her heart. So, with all of that power they are completely powerless. What's special about the 616 Strange, our Strange, is he finally figures out how to move past the loss of Christine, how to give up control, and it was that character growth that saves the universe (So, in a way it was Christine that saved the universe because she taught him that). I think it was a pretty beautiful story about acceptance and personal growth.