Scar Revision or Tummy Tuck to Remove Vertical Scar?

I agree with many of the opinions on this site, however I think there may be another option that you have not considered. You may benefit from liposuction of the abdomen, with release of the vertical scar from the deep tissues, and fat transfer under the scar. This will eliminate the depression that you have from the scar, without creating a new, red scar that will take up to a year to lighten, and give you a smooth look to your abdomen. I am not sure if you have enough skin to make it worthwhile to do a full tummy tuck, but a mini tummy tuck will not really give you the optimum results from my opinion, from what I can tell from your photo. Good luck!

Best Scar Management is important to minimize or completely hide from view, the telltale signs of your surgery—namely, scars. Both you and your surgeon want you to have the most minimal scarring possible. There are many possible causes for scars that are enlarged or not healing well. Unsightly scars are most commonly due to genetics, underlying medical conditions, or improper scar/wound care. The last part is very important and patients can make a noticeable difference in their scars’ appearance by following best scar management practices. Here are some simple tips.
Scar Management tips:Minimize tension on the scar. Steri-Strips and/or surgical tape are often placed in non-hair bearing areas at the time of surgery to minimize tension and keep pressure over the scar.  This minimizes the  stress that  can pull the scar apart (dehiscence) creating a wound and  delaying healing time, and can make the scar wider, or more “ropy”. In the first few weeks after surgery, I recommend the use of Embrace Scar Therapy which is an adherent silicone sheeting pre-stretched when applied so as to offload tension on the scar.Keep your incision site/scar clean to prevent infection. Follow your surgeon’s wound care instructions to the letter with out modification. Never apply different products then recommended without first discussing them with your surgeon. This is especially important during the first few weeks. If there are any signs of infection, contact your surgeon’s office right away and/or see your doctor or his nurse immediately. Typical signs of infection may include redness outside the immediate incision site, asymmetric swelling, and drainage, of pus, fever, chills, and “feeling sick”.Protect your scars from the sun. Staying out of the sun is the best advice. Minimal exposure to sunlight is prevents hyperpigmentation (permanently turning brown) and other problems that can make the scar more noticeable. Sunscreen, at least 30 SPF and an overlying make camouflage make up additionally protects the scar from the suns harmful rays. This advice is especially important the first year following your surgery.Use specific scar maturation products recommended by your surgeon. Patients seem to have their own opinions on this touting everything from Pure Vit E, Coco butter, to Aloe Vera, etc but most have minimal benefit other than keeping the scar hydrated. Although hydration is important there are better, scientifically studied products with greater efficacy. Most of the scientific articles written about this subject indicate that topical silicone gel or silicone sheets work the best. The best product available in my opinion is the Embrace Scar Therapy System by Neodyne BioSciences, Inc. available in many surgeons’ offices. Essentially this is an adherent silicone sheeting pre-stretched when applied so as to offload tension on the scar. For areas that are not applicable for this product (e.g. smaller areas or on the face), I prefer BioCorneum or Kelo-Cote products There are a lot of products to choose from, but silicone should be one of the key ingredients. Although Mederma, an onion extract derivative active ingredient rather than mainly silicone based may help, primarily silicone based products are better and many also contain other ingredients that may be synergistic (hydrocortisone or other steroid, Vitamin E, Sunscreen, etc).. If the reader has problems obtaining these they can call my office. Patient compliance is also critical – use often and according to directions or it will not work optimally. NEVER apply products without first discussing them with your surgeon.Monitor to make sure your scar is progressing optimally. Keep your scheduled follow-up appointments with your surgeon to verify that your scars are maturing as expected.  Occasionally if indicated you may need a topical steroid preparation or even a series of  injections (5-FU and/or Steroids) or laser treatments  to treat or  prevent scar hypertrophy or keloid formation (red raised scars), or other topical medicines to treat post inflammatory hyperpigmentation (brown scars) with prescription creams and possible laser treatments.

An option would be liposuction combined with a scar revision.  This will improve your contours and improve your scar. 

It appears you have an irregular vertical scar from the picture. The underlying muscle may also be loose causing a midline separation or diastasis.
The excess skin below the belly button or umbilicus could be removed through the vertical scar, improve the appearance of the scar, and at the same time tighten the underlying muscle. An additional horizontal scar may allow more skin to be removed. Liposuction could also be performed to remove any unwanted fat deposits.
Consult a board certified plastic surgeon to discuss these options to achieve the best result in rejuvenating the lower abdomen.

There will definitely be a tradeoff between having a horizontal scar and having the vertical scar if you opt for a full tummy tuck. This option would "clean up" the area around the belly button, but the horizontal scar would likely be rather high given that you don't seem to have much extra skin.
The choice will ultimately be yours once you know the pluses and minuses.