The first question to ask yourself is what you’re going for. Are you going for the retro look, or the modern one? Maybe a traditional look or a contemporary one?
Usually, this defining choice would affect the type of accent piece that you will use. There are so many kinds of accent pieces that can be chosen nowadays whether we're talking about lighting or mirrors or a rug, table art, sculptures and much more. It's really just up to you how much are you willing to spend and what exactly are your requirements at home.