I'm liking Fitness+ a lot overall, but my biggest nit-pick is that the trainers don't use words to describe what they're doing the first time they do a move - in anything, HIIT, Yoga, etc., so trying to follow on a TV (Apple TV 4K) when going into any downward position kills my neck, or in a move turning away from the screen, you don't know when to turn back. I tried using my iPad instead of the TV... and the image was too small even there to see what I was supposed to do because the videos are mostly wide shots of the 3 trainers with only the rare side view which is slightly more zoomed in. Yes, I could just watch the video and later repeat it to do it... but why waste the time if they could just say what they're doing like other trainers/workout videos?
I like that we can put together a sequence of workouts for how much time we have or how we feel. But as others mention, there should be an easy way of assembling and saving sequences.
Agree with other suggested improvements listed here - AirPlay please - my living room TV has an old Apple TV 3, which does not support the current TVOS, but could AirPlay from my phone or iPad if the Fitness+ app allowed it.
For the heck of it, I tried a dance one the other day. Years ago, dance type workout videos that I did started with a half tempo introduction to the moves with the next move announced as you completed the previous one. Trying to follow along at full tempo with the moves being announced as (vs before) you're doing them was just an embarassing spastic experience.