Paints can make the fabric thicker, which doesn't really matter on wall hangings.
Dyes keep the fabric softer, and are nicer for bed/lap quilts.
You can add dye to clear aloe vera gel, and then paint them on, they sell little foam applicators...
There are many ways to apply paint and or dye to fabrics... try going to youtube and searching for different techniques, pick up a few dyes (LQS sell some in little jars) and have some fun on scraps :D:D:D