New Slicers - combo boxes and an option for cascading slicers.
Sometimes slicers take up too much screen real estate or have too many members which hinders the UI experience. Searchable combo boxes and a cascading option where slicers only appear if a parent slicer was first selected would help address this and give more option to designers for creating a better experience.
Kenneth Barber commented
If a slicer is intended to only ever have 1 selection at a time, then it can be make into a drop-down list slicer.