The skin patches are generally required when reconstruction is done some time after mastectomy. Immediate reconstructions usually don't require any skin patch since the breast skin is preserved and closed over the flap.
Color differences are usually the result of tummy skin that hasn't seen the sun in a long time showing a difference against the upper chest skin that has low level daily exposure.
This typically improves with time, although a Plastic Surgeon will never encourage tanning, it can help lessen the difference but may also darken scar lines in the first year after surgery. So, we usually recommend protection from sunlight in the first year and your own discretion after that.
Re. Ooph,laparoscopic surgery doesn't interfere with flaps.