Don't forget that AF have already sponsored RO (Tarom) to join up as an associate.
Personally, I think it would be nice to recognise SB (AirCalin) as a proper Skyteam partner - or at least as an associate. After all, they are full Flying Blue and (as far as I am aware) are fully/mostly owned by AF. This would also add considerable qudos for ST-RTW routes, as you would then have trans-Pacific options such as SYD/AKL-NOU-PPE-LAX. But if Air Tahiti Nui join, that may be a conflict.
MH & GA have been on the speculation list for some time, but nothing official seems to have appeared (other than a MoU between GA & KE).
I can't really see both Jet and Kingfisher joining - I guess they are competitiors. But either would be very nice.
And a Latin American airline would definitely be an improvement with the imminent departure of CM (Copa).
But my wish is generally to have as many decent members as possible; be proactive in recruitment, oh ye SkyTeam management board!
--Henry