These specs for setting up your room vary slightly between Dolby and Auro 3D. All of the rooms I have posted use a setup that work with both, a "universal" setup.
The Dolby Institute lays out these specs for Speaker Specifications and Placement in the video I posted in my thread on setting up your room for Atmos.
The Dolby specs also include "Room Tuning". Bryan Pennington, Senior Field Applications Engineer at Dolby Institute, discusses the importance of tuning your room. Some general specs he shares is 60/40 to 70/30 is a good rule of thumb to follow when figuring out how much absorptive surfaces to reflective surfaces to use in your room. That includes floor, walls, AND ceilings. Bryan states:
"Money spent on this type of help (room treatments and acoustics) will be more valuable than ANY piece of gear you will ever buy"
That brings us right back to the title of this thread, unless you have the specs of your room setup and tuning right, the specs of any gear you use in that room won’t matter.