Hot Take: Levi is the best character in the show but NOT for the reasons you think.
Many people would say that Levi is very one dimensional as a character, often being looked at as the ''vegeta'' of the show.
The classic good looking guy who's incredibly strong etc.
Levi for me is summed up as ''one of the few people to stay true to their morals''.
Eren sacrificed the entire world, his own self, put his friends at danger of death, killed his brother, killed his parents, forced his dad to commit atrocities, committed atrocities himself, forced Mikasa who loves him to have to kill him, all to ''see that sight.''
There's many interpretations of Eren's reasons, but despite Isayama's terrible writing, I think this is the most accurate conclusion one may come to.
Armin also killed civilians for 0 reasons, betraying his morals as well.
Jean tried to kill Gabi, Connie tried to revive his mom by killing Falco.
Mikasa supposedly married Jean, a person whom she never loved, while still loving Eren until death, living with Jean while still loving Eren is crazy.
Erwin redeemed himself by sacrificing his dream
Reiner, Bertholdt and Annie you could justify because they were literally 12 when they invaded, but they later on decided to continue with the plan, killing many of their friends including Marco brutally, all so that marley is ''happy with them''
Throughout the entire show, Levi, as far as I know, never once killed or threatened to kill an innocent civilian. Big emphasis on innocent.
He genuinely cared for EVERY SINGLE ONE of his comrades, including injuring himself to save Mikasa, hesitating to kill his comrades even when he knew its already too late when they turned into titans.
Above and beyond he prioritized humanity over his revenge on Zeke, he could have easily smoked Zeke the second time they fought but he kept him alive just so hopefully the plan with Eren can succeed.
Even in the end of the show, he lived giving back to children who didn't have, just like he didn't have anything and was starving as a child.
Overall, Levi is genuinely a ''GOOD'' person, he has very strong morals, and that's incredibly underappreciated in the AOT community.
A lot of the community only focuses on making aura edits about how strong he is, fights, his dedication to Erwin's plans for humanity, but nobody focuses on his actual mental framework.
If the ending was a big disappointment, at least Levi remained consistent till the end.