Go for it, Girl! I did a Christmas Wall Hanging a few years ago, with rhinestones, colored metal shapes, sewn on buttons, glued on stuff....and I love it. I do not actually use it as a hanging, but toss it over a chair where it catches the light from the tree and just glitters! I used the hot fix wand....it works great.
Have had many good comments from guests and friends....and me....lol.
An art quilt can use any embellishment you wish.....send pics....I know it will be gorgeous!