Uhm no? For example Germans in AoE III have like what 3-4 unique units? Technically all of them could be used for 4 different AoE II civs. An unique deck card? You can make it a civ bonus.
Have you even played Malta? Like half their cards are units from existing civs. Their entire commandery building or whatever it is called is filled due to these cards with other civs unique units.
And besides that Malta is a reused campaign asset. The fixed gun isnt new. The sentinel is like the only okayish unique unit. The rest are campaign reuses.
Its true that Italians are fine, but still have some issues. The Basilica feels needlessly big, could have just been a church with the ability to hire the papal units which are just boring units almost exactly the same as other mercenaries but with one ability which on itself is unique but imeadiatly overused.
Also for the previous added civs, Sweden and Inca had yet another house bonus, whereas the Inca are basically a copy of Aztecs but better in everything.
US is the similar to Malta with using existing civs unique gimics through cards and having reused assets from revolution or campaign.
Mexicans and Africans are cool though.