Do it on an 8" step.
Also, just doing all the moves with a lot of energy and as big a movement as you can will take up the intensity: add power to some of the moves that they keep grounded, and go LOW on the squat-type moves; use big arm movements.
You could also do the main section (between the warm-up and cool-down) twice through. If you do that, you might want to vary it by usnig more power the second time through.