Why was his murder case the best one in the series?

Jesus Christ, if you're going to spoil, shave the decency to be right at least.

You didn't even post the other spoilers, like Sigma having cybernetic arms and an artificial eye, Luna being an android, K and Dio being clones, Tenmyouji's first name being Junpei, Quark being Q in Zero Time Dilemma, Phi having Sigma's DNA, Alice's body being made of All-ice, the plot being years after you think it is, the virus outbreak, Jesus man, you suck at spoiling.

maybe she has very expressive eyes

Well they'd have to be capable of displaying fucking text for her to be a mute therapist.
Or maybe she uses a text to speech device. Which would make more sense, but then this is Danganronpa we're talking about.

I'm glad I'm not the only one.
I also want to gently hug Naegi while Kirigiri giggles

Hangman's Gambit was a mistake