I used to think that blank fabric was the hardest to quilt on because EVERYTHING shows.   What I have found is that very busy prints are infinitely more difficult to quilt because the quilting gets lost on the print or looks like scribbles.   I just took out some beautiful feather work because it looked like chicken scratches.  If it would have been on a plainer fabric it would have looked incredible.   So my question is; what do you quilt on busy fabrics such as a 6 to 8 in border?