I think Hellenic world is fullfilled for good, already present ones are enough for now.
Numidia wouldn't be bad choice anyways as one of most important players in western afican coast, plus they outlived Carthage and have given couple of nasty surprises to Romans latter on in time.
Some people often mention second germanic basis faction, maybe that's good idea too.
And on the other hand if Pergamon is in already then why not add Syracuse f.e.???, lots of similarities don't you think???
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