Thank you for the question.
Although it is difficult to give you any specific advice without direct examination or viewing pictures, your breast symmetry can almost certainly be improved upon using plastic surgical techniques. I would suggest in-person consultation with well experienced board certified plastic surgeons.
Asymmetry of scars on breasts
Sounds like a tough call. It relaly is difficult to answer this question without at least seeing pictures. A scar revision may be possible to help your problem.
Breast lift can repair assymetry in some cases
It is hard to say without an examination what the best way is to correct your assymetry, but it is possible from your description that raising your nipple might make you more even. It is worth seeing a board certified plastic surgeon to have a full evaluation and discuss your options.
Breast lift to correct asymmetry
Without a photo it is hard to say but it might be possible to lift your opposite breast and improve the asymmetry. Remember that there will be new scars and you might need further surgery later after children.
Improving symmetry of shape between the Breasts
The only way to responsibly answer your question would be to discuss your exact goals, perform an exam, and review options with you.
I recommend you find a surgeon you like and can trust and visit for an exam.
How to find a good one? Read this:
It sounds like you had SERIAL EXCISIONS of a NEVUS (a dark skin mole which can sometimes degenerate into a melanoma).
Without a photograph to comment on any opinions are forcibly of a general nature. The scar you have will influence the appearance of the breasts BUT the greater the amount of sag, the higher the likelihood that the old scar could be removed with a Breast Lift (Mastopexy). In general, a breast lift brings closer symmetry between the breasts.
You should see several board certified Plastic Surgeons (www.PlasticSurgery.org) and pick the one with whom you feel most comfortable.
Breast lift can correct breast asymmetry.
Hard to be sure without examining you, but most likely your breasts can be made much more symmetrical with a breast lift, perhaps operating only on the other side.
Breast Asymmetry and options
There are many potential options depending on your measurements and tolerance for surgery and the resulting scars. Yes a lift on the normal breast might help but not if the right nipple is "too high". It may require use of an internal of extermal tissue expander to create more tissue. The color of the areola may be reconstructed with a tattoo.
Without seeing pictures, it is impossible to comment on your case. However, breast lift surgery is often used to even out asymmetrical breasts. So, it really depends on how high your areola is. Is it much easier to raise the other areola than to lower the high one. Good luck.
An assymetric breast lift may be the answer to making your breasts the same size. A lot will be determined by where your present scar is and what the shape of your other breast is. Sometimes this my require different size implants along with a lift to get an optimum result.
Seek out consultation with a board certified plastic surgeon in your area and they should be able to advise you appropriately.