"I am sure "size" does matter, at least somewhat. At Stanford, they would not let me leave the hospital until I had a bra on. Their material says that all women are to wear their bras after OHS because the weight of the breasts will pull down on the sternum. But if mine weren't "heavy", I probably would have not worn one after I got home."
I think a soft sleep bra that hooks in the front might work. It did for me. Kinda keeps those things from falling under your arms and pulling on the incision when you lie on your back! Hospital staff insisted I get some soon as I got home. I did - still wearing the same sort - five years out.
I guess the bunch doesn't realize how hot it is in Lantana - no matter what the time of year. Sweat pants just won't do down there. Get some elastic waist shorts.
No matter where you are, who you are with, what you are doing, enjoy every moment, every day. Blessins.........