Best breast augmentation option.

Hello, I had a consultation where a doctor suggested we use some fat from thighs to fill in my breast to improve sagging / stretched out aerola after breastfeeding . Would you reccomend this too? They said cutting would leave large scars. The other option is breast implant behind the muscle as skin is too thin (I didn't pass the pinch test) . Will breast implant look very obvious / fake considering I am thin? It was suggested that an implant that would lead to a C cup would be the smallest that can be used. Thank you for your advice. Ps. I am 173 cm and 53-54kg I wear a 34A bra but not sure if that's correct. under bust 75 cm and bust is about 79cm