I'm thinking we're more likely to get a TSL Europe map, if not "out of the box," than with the Poland DLC. Poland pretty much fills in the only major gap in a Europe map. It's almost like they picked the European civs to be evenly spaced out from each other:
England (Britain), France, Spain (Iberia), Rome (Italy), Greece (Balkans & Aegean), Germany (W. Central), Norway (Scandinavia), Russia, Scythia (Ukraine), Poland (E. Central)
Edit: Also the city state selection helps to fill in some of the smaller gaps: Lisbon, Amsterdam & Brussels, Geneva, Stockholm, Vilnius, Preslav, Hattusa & Carthage (A Europe map would cartographically require some of Anatolia and North Africa.)
I'll bet one of the unknown city states is Dublin.