The fact that the workouts are all so different keeps everything fresh! But let's be honest, like any workout, you can get or give as much as you want, make it competitive with yourself or others, in the end...it all starts with the first step, the hardest part for some, showing up - the "making it to the workout" and that's so much easier when you're walking into a place with a welcoming front desk staff that knows you like family, a group of fellow workout buddies and an instructor that cares you get a great workout.
Intensity of workout. I hate running, but OT has proven that I can do it in intervals.
I would prefer more flexibility and variability with class options during the week, both morning and afternoon. Instead of almost the same schedule every day.