Yes, you do have a receding chin and would benefit from genioplasty. Either option, sliding genioplasty or augmentation genioplasty using an implant would give you the desired improvement in your profile.
Sliding or implant genioplasty would enhance your profile now that your dentition is straightened out.
Genioplasty for Retruded Lower Jaw
For the small amount of chin augmentation you need, both an implant or a bony genioplasty can be done. While there are advantages and disadvantages to either approach, both can achieve similar successful outcomes in your case.
You have a good perspective. The orthodontics has compensated for the lower jaw deficiency so that the 'bite' may get better, but the profile and facial balance does not. A genioplasty can help but it must also increase the height of the chin as well, so a sliding genioplasty is preferred over the implant route.