Good news, you're 80% there. Bad news, next 10% will take you twice as much effort to achieve, then next 5% twice as much again and of course you will never be able to finish the piece to 100% perfection. It's up to you to decide where do you draw the line, so your boss will be content and you don't lose your mind.
I would probably start from looking at better materials and higher quality assets - those plastic towels really don't look great. I don't think you can do miracle with the lighting alone, not in this environment at least.