I have wide shoulders, my mother had - but then she a bottom to balance it all.
If you ask me, you/we/I need to get a can*) to balance, not much to loose on top. About one dress size, like me from 16 to 14... and THAT seems about it. YMMV as always.
Axelle
*) "can" as in: "A girl needs a can" (bottom :-)