What are the odds of a surprise party member in part 3? And who could it be?

Obviously outside of Cid and Vincent.

I know a lot of stubborn fans would probably be angry at an added character (because some people hate everything that is new or different), but I think it would be cool to get a surprise character nobody is expecting. Everyone is of course expecting Vincent and Cid.

If time and space shenanigans happen it could be either Aerith or Zack.

I suppose one of the Turks might join up. But it would be weird to get one of the original 4. Maybe Cissnei I suppose. But she might be too "bland" to be a party member (she's hot of course but her character design is not really as interesting as the main characters).

I REALLY hope it's not Kyrie or one of those types of characters.

I suppose it could be Roche? I wouldn't like it though.

I'm afraid it could be Chadley or some sort of mecha robot chadley. Yikes.

Any other guesses?