Beautiful colors! I would suggest giving the petals veins, and the flower centers pistels and stamens...there are a lot of flowers with 6 petals (though usually then they're actually tepals). If you google flowers with 6 tepals you'll get quite a few and might get lots of ideas for different centers and venation patterns. Might even give you some ideas for some leaves and or vines for between the flowers. One that I found and particularly liked was Clematis marmoraria (its number of tepals varies from between 4 and 8)...it's beautiful! Hope I've helped give you some possible quilting ideas! Whatever you decide, your quilt will be beautiful!