you could even do a simple large Carpenters Star quilt in muted colors. neutral, like beiges, creams, etc.
those always look romantic to me.

What about Key To My Heart quilt pattern. A friend of mine made it and embroidered the couples names, and wedding date on some of the rectangles....

http://www.fatquartershop.com/store/...54&Parent_Ids=

I think any pattern can be romantic if done in the right colors. Or if you're in the right mood. ;-)