R.I.P. Ervin, but I think letting him die here the way he did was the right call, especially since it ended up being his choice in the end, giving his life for his troops. Plus, for once, Eren was right. Armin has become the better tactician and strategist and might actually give them the better chance for survival, all things considered.
also man I wish Bertholdt hadn't woken up right before getting eaten; it was tough enough watching the better of the trio die while Reiner keeps getting absurdly lucky without that
and for some reason I thought the Beast Titan was Eren's dad but I guess not
Erwin was clearly trying to raise Armin up as his successor and I think if he had been of sound mind he'd tell them all to save Armin (I interpreted his knocking Levi's arm out of the way as him being delirious and re-living his past and raising his hand; Levi just chose to interpret it as he did. I honestly didn't like that part of it. Felt too... corny? Cheap? I swear I'm forgetting the word I want here. I think Levi should have come to the decision on his own between Hange's speech, that Scout making it clear this was just going to perpetuate Erwin's suffering, and his own convo with Erwin pre-charge), but I think Levi and Hange had the correct assessment at the moment that Erwin was the better choice overall. Armin is shown as having the higher ceiling though it's tempered by the fact that unlike Erwin it's a bit more uneven and he's prone to freaking out still like when he passed command to Jean there for a while.
And we know Eren ate his dad to gain his Titan shifting powers (after Eren's dad stole it from Historia's sister) so him managing to be alive and the Beast Titan would be a total wtf. ---
xp1337: Don't you wish there was a spell-checker that told you when you a word out?