Her NMTZ is weight lifting though so I don't think you'd want to do that with STS. 30 Day Shred has cardo/weights/abs circuit, so that would be good for a circuit day. I don't think you'd get bored at all if you like endurance/circuit workouts! Hope this helps!
I am not sure what you mean by "weight lifting", but NMTZ is NOT a weight workout. Jillian uses 3 lb dumbbells through the entire workout. I use 5 lbs. It's definitely great for toning and defining, but there is no weight lifting involved. It would not build muscle in any way.
That said, I agree that 30 DS would be good for a circuit day.
Here is a typical week for me using these three workouts....
Two levels of 30 Day Shred (I do Level 2 and 3), plus a 3 mile run.
No More Trouble Zones, plus a 3 mile run
Banish Fat Boost Metabolism, plus a 3 mile run
Cathe Slow & Heavy split, plus a 3 mile run
Cathe Slow & Heavy split, plus a 3 mile run
Firm Volume One
Jillian's Ripped 1000, plus 3 mile run
Start over the next week......
Two levels of 30 Day Shred, plus 3 mile run
Muscle Max, 3 mile run
BFBM
Amy Bento Slo-Mo, 3 mile run
Amy Bento Slo-Mo, 3 mile run
Butts & Gutts, 3 mile run
NMTZ, 3 mile run
I do not do rotations, so what I've just indicated is just a possible senario. I pretty much decide what I'm doing about 3 minutes before I do it, but I try to alternate workout types and upper/lower body day to day.
Also, I don't always run immediately after I work out. Some days I work out in the AM and run in the PM. It gives me a few hours recovery time.