I think you just answered your own question.
On a slightly related topic I am unable to get sound from Apple TV device on the Apple TV streaming app. 5 sessions with Apple support didn’t fix this. I finally changed the audio output settings on the Apple TV device to AirPlay and designated the Cambridge streamer as the AirPlay receiver. No surround sound but at least we can watch the shows on the streaming app. I then have to go back to the original settings in the Apple TV device for all the other apps.
Anyway back to the original question…I would just try both the amp and the streamer and see which you like better