OP, it sounds to me that the pitocin worked just fine, and how you'd expect it to work for someone being induced from scratch. The factors which trigger spontaneous labor are really not well known. We know that the cervix usually gradually ripens and softens over time - from hours to weeks before true labor starts. When you start labor from scratch on an unripe cervix, it can take hours or even days to do that same ripening with just pitocin. When you are induced, the other factors that we don't understand that would have triggered spontaneous labor are not present, and pitocin alone which simply causes contractions can not always make up for it by itself. Once the cervix is all the way effaced (thinned out) and 3-5 cms dilated, and you are in active labor, pitocin works more predictably.
So it sounds like you had a nice response to pitocin, with the cervix being ripe in just about about 7 hours, and you were probably heading into active labor on your own anyway when the doc broke your water - although that may have jump started it.
For a pitocin induction to take just 10 ish hours starting from 1 cm is actually pretty good! So I would say the pitocin worked just as can be expected.