Spaced out breasts, large areolas - least minimally invasive options to fix the shape? (Photos)

It is important for patients to understand that augmentation will "augment" all aspects of your anatomy. The spacing of the footprints of the breast on the chest wall will vary from one individual to the next. Widely spaced breast will appear more widely spaced and vice versa.
The spacing (cleavage) is defined by the pocket. The pocket is defined by the plane of augmentation.When placed submuscular, the medial/middle limit is the sternal origin of the muscle. Wide sternum greater separation of the breasts less dramatic cleavage. This space can be narrowed (with some risk of synmastia) when the devices are placed subglandular or "over" the muscle. There is no muscle obstructing a medial push, however, there is a higher risk of over-dissection and midline migration of the implant (the dreaded "uni-boob").
With regards to your specific question, there is no "natural" way to enhance without weight gain (which comes with obvious drawbacks). Surgically, I would recommend augmentation. You are a reasonable candidate. A wider device might help with your concerns. However, I would discourage straying too far from your BWD.
As always, discuss your concerns with a board certified plastic surgeon (ABPS).

I surely think you would benefit from a consultation with a plastic surgeon. Your situation is complex. Do you want extra volume of the upper poles? I cannot tell if you're left breast is more droopy than your right breast. It is likely your breasts will remain with the same cleavage with almost any operation. You could get an areolar reduction. If you want significant changes, you will have to have somewhat invasive surgery. There are a lot of issues to deal with here, and you might have a much better idea of how you want to go forward after speaking with a plastic surgeon.

Unfortunately there is no natural theraphy to enhance breast volume like hormones etc. Least invasive theraphy can be fat grafting to enhance upper pole and clevage fullness. You have mild tuberous breast deformity and pitosis; best option will be brast lift with implants