While the Seven Years War is a reasonable starting date, it is wrong to leave out the Dutch. Much of New York’s character related to the fact that it started as a Dutch colony, as that led to a much greater degree of religious and ethnic diversity (or rather toleration of religious and ethnic diversity) than the other colonies. It also leave the Indians who had a big impact on 18th century history in New York.
One can only under “why” if you know what happened, and if you know “what” you’ll know why. The issue is whether there will be “right” answers to many subjective questions, as that gets to be a “hot” issue the closer you get to the present.