Most Helpful Girl
I think the weight you are at is fine. As long as you are healthy then I don't see what is wrong with your current weight. For bathing suits, because you are an hourglass you can almost wear anything. Since you have larger boobs though it can be challenging, I am also a DD and I know how hard it can be :P
You could do a bathing suits like these if you like them:
link <something like this is great because it offers lots of support, so you won't have to worry about falling out all the time.
link < this is a great one piece that is still really nice.
link ^ This is another great one piece, and I actually own a few similar to this and I absolutely love them :)
link < A great bikini, lots of support and looks cute too!
This is also really cute: link
It's got thicker straps at the top but a nice detail on them<br/>