I like a simple ballet flat or elegant heel which adds to the overall effect but does not detract from it.
Or, slip into this Women's Vavoom from Steve Madden, a heeled version of a classic ballet flat.
Casual: If you want to walk on the wild side, the leopard print Loveable is a ballet flat ready to be paired with anything from a miniskirt to blue jeans.
Paleo is a ballet flat done in white or black with polka dots.
Some situations simply won't allow for a ballet flat.