I think the fact that the alliance was formed so early is an important thing to consider. They didn't know each other well enough to know if they'd actually like each other. They formed an alliance based on what they DID know about each other. It's done all the time in BB. Women will form an "all girl" alliance, and "jocks" (for lack of a better word) will form an alliance. This has been the first time that it was possible to form a powerful alliance based on race because there were finally enough POC in the house to do so. Honestly, I don't see anything to criticize about it.
In the past, alliances initially formed on the basis of the aforementioned common ground tend to break apart relatively early. The personalities of the HGs come out. They start realizing that just because they share a common bond doesn't mean that they actually like each other. They get to know the other HGs and develop bonds outside of their alliance. Their loyalties to their alliance break down.
I think it's amazing that The Cookout was able to keep such a large alliance, which was formed so early, together for so long. It's all going to be changing in this next week.
I just find this all very fascinating. Sure, BB is very entertaining (to me, anyway), but I continue to learn more and more about human behavior. I don't find it boring at all.