Dbinder, you asked if someone could verify those possible future regional members... well, if someone really could they wouldn't be possible future members but future members....

anyway:

as SAS ownes the majority stake in arBaltic and a 49% stake in Estonian Air with whome they have a close coopeartion, so it's very likely that these two airlines will go the way that Blue1 already went and join the alliance as Regional Members.

Air One is very close with Lufthansa and fully integrated in Lufthansa's Miles&More; FFP. In fact they are the only fully integrated Airline that is not a Star Alliance member yet. But that seems to be a matter of time.

At the very moment Austrian Airlines ownes a 49% Stake in Slovak Airlines. As the Slovak government is planning to sell off the remaining stake in that airline it is highly likely that Austrian will accquire these stakes. A Star Alliance membership is absolutely possible. 

Silk Air is a fully owned subsidiary of Singapore Airlines. I won't comment on that, as I have never heard of them being a candidate for Alliance membership, but doesn't seem unlikely.

Aegean Airlines and Lufthansa started cooperation last year and according to some statements in the German press both airlines seem to be very interessted in Aegean joining the Alliance.

Luxair has strong ties to Lufthansa and Austrian... might not be joining in the nearest future, but would definitely be welcome in the Alliance

Since you removed Qatar Airways from the list of possible members... It's no secret that Star is really interessterd in Qatar Airways. On the other hand Qatar Airways strengthened their cooperation with Lufthansa, ANA and United last year... they are definitely leaning towards Star Alliance.

They are at least as likely to join Star as TAM or SN Brussles etc. to join OneWorld / Malaysia Airlines to join Skyteam