These are the units that I think should be improved:
Comanche Horse Archer: I think this friend deserves a little more power considering that Comanches were excellent horsemen and warriors. He might improve his cadence or damage capacity a bit more.
The Zamburak: He must improve his reach and his field of vision in the late game. (I already mentioned it in my forum, but not as a bad unit, only as a unit to improve). Dragons can reach Rank 14 with the Arsenal. Zamburaks could improve one point of reach at age 3 and at age 4.
The Aztec coyote runner: It is the only “cavalry” of the Aztecs. I think in the late game they should earn bonuses against cannons and guerrillas. I consider that the base damage is not enough. A fully powered treaty faction with dragons and skirmishers and cannons puts them a bit sideways.
Arrow Knight: It does its job well, but it should have tolerance for siege attacks in addition to ranged attacks.
I don’t consider them outdated and that’s why I don’t put them on my ‘almost outdated stuff’ forum. The ones that I would put is the Indian insendiary and the grenadier who, although they are good units in theory, they are not so much in practice.