I was just thinking that Interval Max might be the way for you to go. My logic behind this is that the warm up stepping is pretty basic and you repeat the same small pattern for quite a while so you can get used to it. Then she does 10 cycles where you do a brief step routine, maybe 3 or 4 moves or steps repeated over and over, then she'll do an interval blast and those are pretty much all just a repetitive athletic move. For instance plyometric leaps and jacks, ski jumps, etc. It's absolutely one of the most challenging workouts for cardio you will ever do and it also kills your legs from all the leaping and plyo work.
And another way to go is a new tape of mine I love and highly recommend for people who want tough tough work but no tricky footwork. Mindy Mylrea's Slammin Sports Cardio. It is soooo much fun, but Mindy herself is not one who can handle fancy choreography so what she does is mix in basic step moves (power moves) with athletic activities. It works on your agility, your endurance, your leg strength and it really does remind me of the kind of drills athletes on pro teams use to train in the gym. All very basic moves but tons of fun and easy to follow.
Hope that helps!