I've never seen a female shirt card. I think I'd elongate the card, round corners, and make it in pink and/or yellow -- that would be really feminine. Like the necklace idea -- it would be nice with pearls. The flower brooch is a nice touch.
Single layer Stampin Up heart punch punched through a scrap piece of typing paper and sponged the heart with 3 colors of Ranger distress inks(Scattered Straw, Wild Honey,Brushed Corduroy), stem in Early Espresso and dotted with white Enamel Accents.