As a Brazilian, I like that the Brazilian economy got nerfed recently. It makes the game feels more realistic, more up to date with recent events, you know?
... Wait... This game is meant to be set on the colonial days, not on the modern days? Oh. Nevermind what I said :p.
In all seriousness, on the slavery discussion: All that I can say is, I am really not sorry for anyone that makes a game themed around colonization. Seriously, think about it: If you portray the relationships between the natives and the Europeans realistically, well... Considering how in the original game most civilizations were European, basically, you would be making a game where the players play by conquering and enslaving less technologically advanced tribes. However, if you try to do the approach that devs of AoE 3 did, then one could make a argument-And even a decent one-That, by pretending colonization was peacefull and friendly when we all know it wasnt, you are being disrespectfull to the descendents of the remaining Native Americans. It is kind of a "Choose precisely how you wish to be offensive" scenario.