first i will answer with a question.
Have yu ever played rome total war and being cetls or german or numidian and wanting to destroy the regular troops of rome?
and some facts
most colonies were created after 1800
except from british
ottoman empire never realy destroyed by europeans in battle
but throught diplomacy
many non europeans and nonamerican caused serious problems to those wanted to colonise them (after 1800)
by the era starts most europeans were just fighting the one against the other.
We do not hate europeans factions just prefere to play first with no europeans because is a greater challenge to fight europeans with their owns powers and try to hold their lands (maybe victory condition).
if natives are so weak as yu want then yu get bored.( as weaks was celts and numidians in rtw)
and most colonial wars lasted for more than a year and after 1800 most of them happened
siam ethiopia the state of sikhs persia and ottoman empire barbary states
by the early 1800 (the games ends ) were prety live and kicking.