the installer, Audio Breakthroughs in Manhassett, NY did a fancy ARC computer room correction
Great, then you know you are setup correctly.
As for sources it depends on the files you use. If you are using discs (CD,SACD, BRD,UHD, etc) I would recommend a Sony X-800M2. The Panasonic player is nice but lacks the SACD features of the Sony.
If you are using files that you have ripped and stored on a NAS I would recommend the Zidoo Z9X media player, fantastic device,
If you want to stream Netflix, Amazon Video, Disney Plus etc. if you are in the Apple ecosystem get the newer ATV 4K. The Firestick has poor SQ and is crammed with ads. Nvidia Shield is swamped with google ads. The X-Box Series S or X are superb for both streaming and gaming. If you get the Series X you also get a blueray player.
The Anthem piece is superb, you will really enjoy it. As for video I use an Epson PJ in the media room and a Sony 4K TV in the man cave.
After your system is well broken in and you have the sources you like the first upgrade I would do (even before adding two more height channels for atmos) is getting a second sub. It isn’t for the volume of bass, its for the smoothness.