I haven't tried SP meter.
What I definitely noticed, when I run those Dolby Atmos demo files, that my front stage is noticeably more dull/flat then my surrounds and top atmos. Theres no life in them, no punch, while surrounds/tops sound amazing.
Fronts are Kef Q300+Q600 center, surround left/right is Kef Q100, surround back are some small Polks T15 bookshelfs which sound surprisingly nice on their own, and top 4 are Micca 8C in their own enclosures I built, that also sound actually incredible (I tried them on my desk once I finished their boxes and couldnt believe the sound)
All speakers are similar sensitivity and power requirements.
Why in a gods name is front stage lifeless is beyond me, its like theres a blanket over them. I do run front left/right with Fosi V3 with 48V supply, but center channel is direct from receiver so at least center should sound the same. Speaker layout is close to perfect as per all recomendations for 7.1.4.
I definitely have some tinkering to do to figure out wtheck is going on.