Levi's rank in the survey corps

This is a really interesting question. Here's what I think. He always seemed more like a follower than a leader to me. Throughout the entire anime, I always see him take orders from Erwin and led his squad to achieve said orders. Some examples being capturing the female titan in the forest and the entire Eren and Historia situation in the Uprising arc.

Hange was chosen because how innovative and intuitive she is. She came up of the idea of thunder spears to fight Reiner and the titan guillotine. She spent more time studying titans than anyone else to figure out different ways they could approach the titans. She figured out the walls are made of hardened titan skin and came up with the idea of Eren hardening his titan to seal Wall Maria. She also found out that Reiner and Bertholdt are hiding in the forest when they captured Eren.

Armin was chosen because of how strategic he is. Sure, he isn't as charismatic as Hange and Erwin, but he did come up with a plan on how to beat Bertholdt. He came up with a plan on how to seal the hole in Trost and figured out how to minimize casualties. He knew that the warriors prepped an ambush for them at Shiganshina and knew they should check inside the walls. He also had some practice in leading large groups during the RtS arc, commanding a large group of soldiers to check the walls and commanding the 104th. He also pinpointed the weaknesses of the odm gear that Kenny's squad uses.

Also, if Levi was commander, I can totally see him telling people to make their decisions that they'd regret later on in life.

/r/ShingekiNoKyojin Thread