Of those three, I'd say the last is hugely important. The only other ape that pair-bonds is the gibbon, but gibbon males and females are the same size, which is what you normally find in animals that pair-bond, so we're doubly unusual in that respect. Humans are very likely to have evolved pair bonding from some situation along the line back to our common ancestor with bonobos/chimps where it was not the case, and we're not as strict about it as gibbons, even now.
This study suggests that pair-bonding in primates evolved as a means to prevent male infanticide. I'm always a little wary of studies that run models in case the assumptions of the models are off in some small but crucial way, but it's an interesting finding. The evolution of monogamy is quite a thorny issue, generally.
Another difference would be division of labour. It was once thought that bonobos didn't hunt in the way chimps do. It's now known that they do hunt, but unlike chimps, bonobos hunt in mixed-sex groups. There is very little division of labour by sex role in bonobos.