Use dollar tree flickering, battery operated tea lights to illuminate. User silver, metal spray paint on the exterior and while wet, misting it with a vinegar/water solution. Using a clean rag, dab at the bubbles that appear and then let dry.
Paper Towel and TP roll candles are great for floating candles, because they are so light weight you can hang them with just a tac. You are right the imperfections are unnoticeable in the dark. I want to make some black ones now that I see yours.