A full on tummy tuck would be the best surgery to improve your self image. Your midline abdominal scar is only one component of your post pregnancy abdomen. The whole Mommy Makeover concept is not only to get rid of the negative, i.e. your butt-like looking abdomen, but to give you a positive, i.e. a flat abdomen with a nice looking belly button and a thin, well hidden abdominoplasty scar.
You asked the question, is there something other than a tummy tuck that can get rid of the butt-like looking abdomen. The answer is yes, surgically, one could use a "pickle fork". This is an instrument which could be used to separate your midline abdominal scar from the deeper tissue. It would get rid of the butt-like look quickly and simply, but it wouldn't give you the flat stomach, attractive belly button, etc.
Regenerating your self esteem comes from not just removal of one problem, i.e. the dent that creates the butt-like look to your abdomen, but by truly giving you an attractive abdomen that you would be willing to take to the beach in a 2-piece bathing suit.