I’ve done a good deal of her stuff over the years and I have all her videos on dvd except for the one where she uses a weighted bar. Triple threat and Sculpture are her hardest because she spends more time on each muscle group. Most other workouts are less time and consistent across the videos. So if you like Unplugged (and I do too) you’ll likely find any one of them to work for you.
I find her workouts to be safe, effective and sustainable with that added bonus of scalability (the ability to increase the challenge with added weight). I think adding weight is the key here to go to that next level. Most of her workouts have similar characteristics and I haven’t thought of any as mid level per se.
I hope you continue to enjoy.