Personally I think making, or buying, a gift for someone without gearing it to their likes and dislikes, taste, decor, style of living, and personality...especially when you know these things for sure...is just plain wrong. Gifts are about the recipient, not the giver.
There are hundreds of fabrics, blocks and quilt patterns that fit the description you have given of your family's preferences and that would not compromise your style at all. Quilt blocks are about value and contrast more than fabric color and print. You could do most of them in shades of gray and they would be just as effective. Limiting the colors actually makes the pattern stand out more than the fabrics. If in doubt, look at the Amish quilts, the Gee's Bend quilts, Denyse Schmidt's quilts.