I like the three man fire team Idea. Honestly, I would like that more than a four man fire team, considering that there are Three races, and three classes. I am someone who likes to be in a diverse team of people. Three warlocks and a titan in a fireteam would annoy me. There are three classes, so it would have to be imbalanced if there were three different classes and then one more of one as well. I have heard some people say that there should be six people in a fire team, but in my experience, more than four is too many...