Well, I pretty much had the same general idea except, The beginning story "Arc I suppose" would be different, Earth wouldn't be destroyed and almost every race got owned.
I'm really not sure about my opinions on this... like, what I was going for in my initial plans was the same thing I said about fifteen times plus the word greedy....
You really didn't need to change it, but if your happy with it then it's fine. The thing is, how would we know that the surrounding aliens would have the same logic as humans?