It looks like a good start.
I don't see a lot of evidence of the required wiring, but may be I'm missing something.
Properly laying conduit is crucial. Designing the ground place of the theater is also crucial. Proper attention also needs to be devoted to protection and also Ethernet distribution.
These rooms are a lot of work. I just built a
new one last year and two other systems besides. We sold our home on Lake Benedict MN and built on in the Twin Cities metro.
AV theater
In Wall System
2 Channel System.
I note you have a lot of hard work left before completion. Keep us updated on progress. It is always fun to sees these schemes progress!