I am short with big boobs and a fat tummy so for me it's Closet dresses. They have high waists so hide the tummy well and can contain my boobs. I'm so bored of them now though as I own almost everything they sell so I'm looking for inspiration.
I think I'm a similar shape, I have a few closet dresses although their sizing can be a bit erratic! I tend to get on quite well with French Connection stuff for workwear, sometimes Fever, Hobbs occasionally, I've also got a few more casual dresses from Yumi. Ted Baker and Karen Millen both have the odd success, as does Oasis from time to time.
I'm currently eyeing up a dress from Blonde and Wise, not especially workwear but fancy one anyway!