So! Metin and I are probably going to be canon updating Alto and Ranka in the very near future, so here's a couple things that are going to change. Overall, it's not like her personality will be ~*drastically different*~ but there are a few subtle differences!
1) She'll have regained all her memories of her childhood. This includes: being Ranshe's daughter, being Brera's little sister, living on the 117th Research Fleet and such.
2) Tying in with 1, she probably won't react as badly to violent situations as she has in the past (read: random dead guy on beach day), but she'll still be pretty scared.
3) Some new songs: Aimo OC (probably won't be singing that), Anata no Oto (Your Sound), Ao no Ether (Azure Ether) and Lion. EDIT: Might as well tie in the super awesome medley, and also Triangular.
4) RIP Michel ;_;
5) She'll be firm in her resolve re: I LOVE ALTO-KUN. In fact, she'd already confessed to him but oops eloped ran away with Brera soon after. Thiiis is actually pretty complex as Alto never chose either one of them by the end of the series, but I interpreted Ranka's "I won't lose to you in song or in love," to Sheryl as something as an acceptance of Sheryl and Alto's rabu rabu relationship before going off to the Vajra planet, but at the same time she's saying that she won't lose. If that makes sense? Basically it's like I KNOW YOU WON BUT I WON'T GIVE UP--
6) Err, new clothes?
*_*? *A*? 7) Ai-kun might possibly
cease to be adorable but I'll probably keep him adorable. ;w;
8) Significantly more gay for Sheryl.
And as for Alto... he'll be a lot more gay for the sky, and hold both Sheryl and Ranka to more importance but still be a douche and not pick between them though he was in a somewhat relationship with Sheryl after Ranka eloped with Brera. *A*; Also, he's wearing her earring on one of his ears so please feel free to poke more fun at him.
... Umm yes that's all I can think of off the top of my head so remind me if there's anything I'm forgetting!