...although given the Oppo's streaming features, I fail to see how the Sonos Connect adds any value to your proposed setup.

You may find the preamp stage in the Oppo is inferior to the Rotel. I just tested this in my system. I have a PS Audio DIrectstream DAC which has a preamp stage. I tested it send a direct signal to my amp vs through my preamp and it sounded obviously worse without the preamp.

You would think that eliminating a component and going source to amp would be better but that is not always the case.

fruckman wrote:

Oppo's new UDP-205 drops the steaming apps that were on the 105 (i.e. Tunein Radio, Pandora and more). My existing Sonos Connect includes those apps. I've considered buying a preowned 105 for this reason and selling the Sonos.

Does Sonos offer exclusive apps/services that aren't available via phone/tablet/computer?

I assume that you meant me when asking if I am happy with the Oppo. I don't have an Oppo. I did the same test with my DAC which is a PS Audio Directstream. I am not saying the oppo definitely has an inferior preamp stage, I would just try and do some listening tests as you may like one or the other.

https://www.forbes.com/sites/johnarcher/2018/04/02/oppo-shock-popular-av-brand-announces-that-its-time-to-say-goodbye/