Banded KB swings! Have done these in Crossfit a few times, and they work. Adjust the thickness of the band and height of the swing for intensity variations.
American KB swings! (assuming you’re doing Russian now). These add another element and are harder than Russian swings at a given weight. These are often part of a Crossfit WOD.
One-handed KB swings! I did these when I followed a Pavel program. In his Simple & Sinister book he outlines how to progress with these if you want to stick with KBs.
I think the two really compliment each other, and no need to do only one or the other. I like adding KB swings and variations as part of a conditioning circuit, done at the end of a barbell session or as a standalone session. The banded swings are best done more as a strength movement and not as part of a WOD or conditioning session, due both the explosive nature of the movement and the logistics of setting it up if moving quickly between exercises.