Remington being a good guy as always. Nearly everything he does is to teach Rosette. This time by aggravating them he taught Rosette to stand and fight for what she has faith in no matter what, and Chrno to fight with a tranquil mind so he could overcome Aion.
And Remington cut off Chrno's hair! Yeah sure as proof he 'killed' him but at the same time I'd wager it's a sign of Chrno's development. The hair cut motif where a character will have a visual change as their development into a new person starts. This Chrno now able to confront the past, fight to the end with Rosette, and one able to control himself... or something.
Stella somehow knew about a demon teleporter but I guess she could have done some jewel stuff to figure it out. Still, pretty convenient for there to be a teleporter to Eden and a recording capability on a jewel like that. But, she did know they'd make their way there so it's not a huge deal.
I can't help but feel going to the enemies base like this is rushed. We just heard that we now know the enemies base because the demons are all going to it or something with no build up, and there's a teleporter right there. If this is a trap or something it will make more sense why it's so spoonfed, but otherwise it's rather rushed to spend so much time building everything up slowly and then give the characters everything they need last second.