I'm afraid I'm too much of a pacifist myself to buy into the notion that primitive humans were basically hostile and warlike to each other. As I've said before, excessive hostility wouldn't have been a big species survival trait. And without the kind of population pressure that besets our "civilized" society, I doubt that it would have been likely, either. Humanity is basically a social species, banding together in great part by choice and innate predilection as well as necessity. I won't dispute that antagonisms between individuals or even groups very likely existed, but my feeling is that they were more probably subordinated to the cooperation needed for survival in that era, when humans were but one of many species vying for the same resources, and individually were far from the best physically equipped to succeed.
In any case, that's my viewpoint and I've chosen to impart it to the prehistoric world I've postulated.