As far as I know all European civs, Asian civs and USA has access to powerful mercenaries:
Mamelukes, Jaegers, Elmeti, Fusiliers, Manchu…
These units shipped in age III or IV can sometimes win a game for you if well used.
What native civs have instead:
- Comanchero, Pistolero, Renegado always available in Native Embassy - outlaws units taking 4-6 population space - lets be honest - no one will ever use it
- Shipments with allies - Zapotec Lightning Warrior, Maya Holcan Spearmen, Cree Trackers… - These units are not stronger than any normal Commerce Age/Fortress Age units. Their advantage is that they are not taking any population space.
I know that this is a design of a native Americans and probably will not change much. However I just want to express that using powerful mercenary units is funnier. If you are playing against let say Ottoman player and he is sending Mamelukes in early Fortress you need to show them a little respect and focus them down otherwise you will lose. Native Americans can’t threat you that way.