My kids don't really care for the typical calicos...but they love the geometric and other different types of prints.
They are also not big fans of traditional blocks, but love some of the more striking PP blocks and the contemporary style quilts too.
Maybe working with several colors, but add in different shades of them? to increase the amounts of fabrics?
OBW's maybe, or box in a box with 3 colors is very contemporary looking too. Cube quilts? Bargello in just 3 colors with different shades?
What about blenders or tonals instead of prints? Much more subtle than prints?