I love Susan's DVDs as well, particularly the latest release. You might check out KCM's boxing/kickbox workouts. TLC is one of my favorites and there is Circuit Burn has a couple Boxing/KB premixes (the circuit workouts are great, too).
This morning, I did MMA Kickbox, which I enjoy more every time I do it. Wear weighted gloves with it, and the leg conditioning drills between the combos are great. I hope Cathe puts out more KB or Boxing workouts in the future. Hard Strikes is a treat for me, I do it during my long, non-flex day work week to make a 45-hr workweek more bearable.
There are lots of options, if she does a Greatest Hits focused on KB and Boxing. Premixes focused on shadow boxing, heavy bag work, kicks/blocks, low(er) impact, drills, conditioning from all the ab/core segments, etc.