Almost all of these suggestions are extremely specific 1-2 map natives. They would need to be more broadly distributed (at least 5 maps) to be a viable pick. And Romani could absolutely be an option.
Here’s a few examples of ones that are widely spread enough to fit nearly all of Europe:
Romani Caravan
Region: Anatolia and all of Europe
Units:
Romani Vagabond - A fast stealthy unit that excels against mercenaries and heroes (Native equivalent to Spies and Ninjas). There’s probably some better names for this, maybe Romani Rogue or Romani Trickster
Vardo - A Romani wagon (Native equivalent to the South African Trek Wagon)
Upgrades:
Tinkerers - Ships a Tin Mine and improves coin gather rate
Nomadism - Economic units move faster and have more health
Fortune Tellers - Temporarily reveals your opponent’s line of sight and increases the Vagabond’s line of sight
Hansa Kontor
Region: All of Northern Europe
Unit:
Reiter - Light ranged cavalry with a 1.5 rate of fire
Upgrades:
Trade Privileges - Trade route yields increased by 30%
Trade Embargo - Temporarily blockades an opponent’s shipments
Free Cities - Defensive buildings are stronger? Suggestions?
Catholic Monastery
Region: Most of Europe
Unit:
Hospitaller Knight - A swordsman unit with high health and siege resistance. Siege resistance would represent their presence at many historical sieges such as at Rhodes, Malta, and Candia. The resistance would be more suited to resisting building and ship fire than for taking on artillery.
Upgrades:
Christian Schools - Same as Jesuits
Flying Buttress - Same as Jesuits
Holy Orders - Something similar to the Ignatian Spirituality card that Ethiopia has (would synergize well with Hospitaller Knights)