Not sure if this would help - I noticed about two months ago that my 11 yr old son (anxiety disorder - looking at a possible Obsessive Compulsive Disorder (OCD) - defiant behavior at times) was most difficult to deal with after 7:00 at night. So, I came up with a point system. On a poster board, I listed ways that he can earn points. 25 points for going until 3:00 without loosing points (not too much trouble during that time frame), 10 points 3:00 - 5:00 for not loosing points, 10 points for 5:00 - 7:00 for not loosing points, 5 points for 7:00 - 7:30, 5 points for 7:30 - 8:00, 5 points for being asleep by 9:00 pm. A list to loose points: 50 points for annoying 17 yr old sister, 50 points for disobeying to the point mom starts to scream, 25 points for touching the car doorhandle or unbuckling before car was parked (because that was becoming an issue), 10 points for annoying classmate, ect. A third list with a lot of chores that can be done to earn more points (wash bathroom floor, pick up clothes from bathroom floor, ect.) These were all little items about 5 -10 points each. Also included points for showering/bathing, brushing teeth, ect. The fourth list was a list of rewards to turn in points (100 points = $1.00 or donut from local bakery, 550 points = bowling or movie, etc.). This worked like magic. My intentions were to hand out the points throughout the evening as each timeline was met. My son instead started looking at the list about 7:00/7:30 pm, calculating what he has earned and planned on earning and then deciding which chores he wanted to do before bedtime to earn more points. Our evenings turned from ugly arguing to relaxing time of child being very positive about the bed time hours and making sure he was asleep by 9:00 to get those extra 5 points. If we were home after 8:45, he was given 1/2 hour to get to sleep. I introduced the list by saying, "I have noticed that after 7:00 pm if you are not getting ready for bed, you have a hard time listening and obeying. We then end up arguing and fighting. I don't want to argue anymore. I have come up with a way to help us make night times more positive."
I guess I don't see rewards as bad - he is earning an allowance - when family life goes well, good things happen.
Bribes in my books are stricter - and more "at this second" - do this now and I will give you something. The above is more like a list of everyday expectations that has a consequence if not met.
I have a hard time determining consequences for various actions so this helps me and my son know ahead of time what a consequence will be for bad behaviour.
You may try focusing on morning times as well as after school times, anytime with siblings.
Chasity is right on also, anytime we can get our kids to talk about their difficult issues, the more they seem to see how their actions are affecting others. It gets them to think about what just happened and how it could have been different. It is teaching them problem solving skills. I am trying to teach my son the difference between personal and objectional. When he has problems in math, he wants to blame his teacher instead of looking at the issue and listening to how to understand something. He is angry so instead of looking for ways to understand, it is easier to place that anger toward a person.