If the currently selection of The LEGO Batman Movie sets is not enough to satisfy your need, there’s also a few other on the side LEGO Batman Movie polybag sets as well. There is The Joker Battle Training set which includes a Joker minifigure as well as a Bat Signal Accessory Pack. Images are taken from Amazon.
LEGO The Batman Movie 30523 The Joker Battle Training Polybag Set
LEGO The Batman Movie 5004930 Bat Signal Accessory Pack