Can you pad the bottom of the bra so your breasts sit a little higher in the cups and take up the slack in the sides? (I am so lazy that I always try the easiest fix first).
Personally, I loath halters because they hurt my neck, but have a problem keeping a regular bra strap up on my left shoulder (don't ask why not the right one, I don't know). I used put a cross strap high up on my back under my hair to connect the regular straps, decorated to look like it belonged there, but now you can buy those invisible straps and do the same thing with less effort.
|