You could also argue Alexandria which was the 'Filiki Eteria' main goal.
And maybe Greece could be formed with just Achaea, Morea and Athens as originally it was formed with just the first two.
Yes, possibly you would just need Achaea, Morea and Athens to form Greece. However if you are in possession of areas considered part of 'Greater Greece', i.e Thrace, Smyrna, Sicily, Alexandria, they become instant cores. In an alternate history scenario this could have been a reality anyway.