In true jam band form they always play different set lists so that is not new, Metallica famously made fun of them and then decided to start doing this as part of 2 show runs:
Phish also have by far the best light show out on the road now so it will be interesting to see how they incorporate this into the Sphere shows.
Rumors are that some acts approached are afraid to play the Sphere, pop acts in particular are worried the stage is set up so there is basically no where to hide and that the sound is so good any lip synching or fake instrument playing will be exposed quickly. A few of acts I think could do well in this type of venue:
Tool
Pearl Jam
The Cure
The Killers
Zac Brown Band