Get a bunch of arcade machines! They're a common piece of furniture, so it shouldn't be too hard to get your hands on if you don't already have one.
Have a rest corner! Get a few pillows or chairs and a low table so that arcade goers can relax. Place a potted plant nearby for decor. And throw in a water cooler too if they're thirsty!
Hang up pattern paintings based off of arcade classics like Pac-Man!
Add one or two fortune cookie items for accent, like a coin.