zomg you cut the part that has Steph trainsurfing! D: Robinly traditions enacted in advance when she won't have the occasion to do so in canon as Robin, due to writer phail! *freaks out, quietly*
I think the girl in the picture with ghost!Steph is Ariana.
Squeeeeeee! It's so cute seeing them team up. So cute how Cass obviously takes to heart Batman's "in these streets, you are me". And zomg Steph is spunky and determined and maaaan, I wanna read about the friendship of Cass and Steph forever. This is a much nicer vision of the Cass-Steph friendsdhip than the one Dixon wrote in Batgirl 30-33, imo. It took me a while, but I ship them a lot now.
The two pages where Cass wants Steph to read the note and Steph is "...what if I don't?" are excellent storytelling. Expressive art, nothing gets in the way...