Currently have gum disease, am I a good candidate for gum contouring? (Photos)

Hi, I currently have really bad gum disease and I am looking to have veneers. I was told that before I can have the veneers, that I would need to have gum contouring completed first which was advised by some of the dentists I saw whilst other dentists I saw said it wasn't necessary to fix the gum disease I have currently. Some suggested a deep cleaning and periodontal treatment. However do you feel I would benefit from gum contouring, especially with the section on the left?