I swear this is the last one... The Arcee bots referring to themselves as 'Arcee" could just be their team name. Naybe the red toy that we saw is Firestar who takes Arcee's place after death. They are sad about it and want a way to remember her, so they name the big bot that they combine into Arcee and that is also the codename for their squad. It would make sense I guess.... otherwise it is as we have all assumed.