I have a similar figure too oxocube (but with a bit more of a tummy!) so well aware of the big boobs problem.
I think with opaque black tights and a scoop neck dress that isn't too low cut you don't look too slutty but you do need to try on the dress as the extra breast can make them too short in my experience (hence why I only window shop online )
With the halternecks, boobs are going to look pretty big but they are knee length and with a cardi, big belt etc I think it can look sexy without too slutty.
I personally think that it is best to work with your breasts as I find that covering them up tends to leave things either hanging off them - making me look pregnant - or just silly and still massive, just hidden iyswim. A strap top under dresses is my friend on these occasions .
Good luck OP, it's a thankless task trying to find the "perfect" dress whatever your figure! Let us know what you get.