Honestly I wouldn't be surprised if it was Tiki, since they seem to be liking filling out games and she could be any color. As to who I want Hector, Sigurd and Dimitri are the only 3 I actually care about as characters, though I wouldn't mind Veronica but I am betting on her showing up near Brave Alphonse. If they go with the order you get the emblems then it would be Celica, but who knows if they will do that since I don't see them waiting that long on Lyn. Finally giving Celica her Awakening tome would make her green so it is possible.