Some online fabric store sites have a design wall feature that lets you select the fabric photos and put them on a virtual design wall. That way you can put up your Moda panel and select others that you think will go with it and then play around to see what works best for you. As lillybeck said, no quilt police here. Do what looks good to you.
Edit: I just checked my list of Favorites and found one website that has an interactive design wall:
www.quiltfabriccloseouts.com, which may or may not be helpful. Failing that, you could try putting things in a virtual shopping cart and then comparing them. Hopefully someone else will have a better solution for you.