Another thing I had thought of was waking up for Daily Life at some point, and engaging in the usual events with a slightly different internal monologue and ways in which characters interact with you. And then you discover that the character you had been playing up until that point has been killed.
Though I think for Danganronpa 4 it's best if we stick to a female character for the entirety of the game haha.
Also as definitive as that ending feels I still think a 4th game is definitely coming. A new writer perhaps but I'm always ready for more Danganronpa.