J.H.
Pulling off of the breast could be a sign of an overactive letdown. The milk comes out so forcefully that the baby can not always handle it. They pull off and arch their back as if in pain. A foremilk/hindmilk imbalance that sometimes comes with this can also cause gassy babies. Baby fills up with the more sugary watery milk and not the more filling fatty hindmilk. The more sugary milk causes the gas. As you said all babies are different and each time you breastfeed it can be different as well. I had an overactive letdown with my first but no issues the second time around. Both of these issues will resolve themselves with time. It can be frustrating for the baby and the mother in the meantime. I found the La Leche League website has some helpful suggestions if you are having issues wtih this. In terms of being agitated in sleep, I found that sleeping like a baby didn't always mean peaceful and quiet.
Good luck