From your frontal view, you seem to be a very good candidate for a tummy tuck. You're thin, with very little excess fat. As you mentioned, though, you have loose skin, stretch marks, and an abnormally-shaped belly button. In addition, there's a visible gap between your midline abdominal wall muscles, which probably causes a bulge which is visible on your lateral view. An abdominoplasty incision would be designed low, within the bikini line - you would also have an incision around the belly button. The midline abdominal wall muscles would undergo a plication (tightening) and all of the loose skin would be removed. The belly button would also be reshaped. As I stated earlier, you're a very good candidate for a tummy tuck. You would benefit from consultation with a board-certified plastic surgeon. Best of luck.