I really like these: (not necessarily in this order!)
Tracey Mallett Pilates Super Sculpt
Do More Pilates Mat Series
Do More Pilates Standing (these two, I find to be quite challenging)
Karen Voight Total Body Training (it uses the ring)
Karen Voight Abs and Back
Winsor Pilates 20-Minute workout (this has been my go to, short Pilates workout for years now)
10 Minute Solution:
Pilates
Quick Sculpt Pilates (uses the small ball)
Kathy Smith: Fat Burning Pilates (Pilates for Abs, and Lower Body)
Almost any Ana Caban Pilates workout!
I also like Robin Long (Balanced Life), and Pilates Happy Hour short workouts on YouTube.
Sherry