The majority of my bras are functional (smooth/seamless in either nude, white or black) and can be worn under pretty much anything bit they are so dull and boring.
So many pretty bras available now for DD+ sizes (bravissimo/curvy kate) in an array of colours but not smooth cupped so the 'imprint' of the fabric can be seen under t shirts, vests, jersey dresses, blouses.
If you almost always wear bras that are gorgeous rather than just plain functional what do you wear on top?