I’m a huge supporter of having Oceania introduced: the last inhabited and penultimate ‘European explored’ continent must be tackled in AoE3! It would be the logical, next horizon to address, after Asia, Africa and now Europe are covered.
I equally agree on the two potential civs, the Māori and the Hawai’ians: I’m convinced they gather all the conditions, thematically and time-frame speaking, to be candidates.
I had actually included them in my potential civs review here and there (forum)
Moreover, they’d certainly offer very interesting gameplays while the new maps would represent wonderful places