I should first introduce myself as the author of Donnacona's Dream, which is a TL which wanks by the St. Lawrence Iroquoians (who were the northern 'cousins' of the Iroquois who lived in the St. Lawrence Valley, but were exterminated OTL some time between 1540 and 1600). I have also used the idea of European migrants becoming adopted into the nation, and helping to spread new ideas, although in Donnacona's Dream it's really not European migrants but their Métis descendants who have the most impact.
One thing I would say is that wikipedia is particularly unreliable when researching pre-colonial and early colonial Native culture. The issue is that there aren't a lot of written records available from Northeastern North America from the 1500s and 1600s, and that those records that are available are often written by highly biased sources such as missionaries. What that means is that there is no historical consensus about the time period, and so there are wildly contradictory competing stories about what happened. Some are based on the scattered written primary sources, others on archeological data, others on oral history.
What I would recommend is to go to your local library (ok, maybe the central library of the largest nearby city would be a better bet), and search the catalogue for "iroquois". Then, check out the three or four most recently published books and read all of them. It really helped me to get multiple different pictures of what was going on so I could form my own opinion of what story to believe.
Of all the books checked out of the library, my favourite was Iroquoian Women: The Gantowisas by Barbara Alice Mann. I think I found it the most helpful partly because it told a story that none of the other books did (and Wikipedia doesn't, for the most part), because almost all of the other books were written by men and based upon male sources. The nature of iroquoian society was that it was divided into a 'male sphere' and a 'female sphere', and the two halves of society had this sort of separate-but-equal thing going on. Most traditional histories focus on things like warfare and grand councils, which fall completely into the 'male sphere'. This is mostly due to the fact that 95% of literate people who had contact with the Iroquois at the time were men, and they were simply not allowed to be a part of the 'female sphere', so there are very few written sources about that 'female sphere'. Iroquoian Women: The Gantowisas was the only book of the ones I read that really did the 'female sphere' justice.
Ok, I should also say that I am a feminist, and that one of the reasons I wanted to write my TL about an Iroquoian society was because I was interested in having a much earlier development of feminist ideas, and thought it would be interesting to have these feminist ideas come into Western culture from Native culture.