Reformer Pilates Flows

I've been teaching for over a year now, and as much as I love it, I still find myself getting anxieties about repeating routines and flows. I know that repetition is good in order for people to see results and improvements, but I worry that people are bored or they will notice they've done the same thing before. I currently try to plan two sessions per week to alternate between classes. Has anyone got any tips or ideas?