I usually only flock the inside of a box when I’ve done something inexcusable, like a gouge I can’t sand out and can only fix with a little wood putty. When this happens, the flocking does a great job of hiding the boo-boo. When I spend two hours making an acorn box out of ambrosia maple, I find it hard to just throw it away. If it’s a piece I intend to sell, I do drop the price a little.
My color preference is dark brown.