If you like mystery quilts, there is a link from the QOV site to a website that has over 30 QOV mystery quilts.
I usually use red / white / blue fabrics in tone-on-tones or small prints. But, if you're making the quilt specifically for a veteran you know, like a friend or family member, then take their likes and dislikes into consideration. For example, I'm making one right now for my daughter who spent 8 years in the Marine Corps, and it's made with a batik jelly roll with lots of colors. We are doing a QOV night at our guild and the Regional Coordinator will be there to talk about QOV and to accept quilts made for donation. And we are inviting our friends & family who are being presented quilts.