You already have the answer

You have already answered your own question.  The skin looks this way now because of poor skin elastisity. Treatments to tighten the skin are unlikely to give you the desired look you want, because the photograph demonstrates quite a bite of extra skin. In this case I believe the only way to achieve an improved look would be to have the skin removed. This would require a tummy tuck. The scar could be hidden very low on your abdomen, just above the pubic hairline where it is easy to hide. I think you will be disappointed if you go ahead with any lesser procedures.

Good Luck!