Unfortunately there are so many variables at work along with challenges in identifying supported protocols and formats, what starts as a reasonable and straightforward question is difficult to answer in the same way.
Speaking for my own set of priorities, picture quality has to not outright suck to be acceptable. That roughly translates to 1080p for movies and 720p for TV shows. Because I mostly use Plex and Netflix, I like the current Apple TV4 best for the Plex implementation. The remote is a disaster, but the worst parts of it can be mitigated with a bright grippy cover to stop it slipping between couch cushions and to be able to know that you're holding it the right way without turning lights on. Unfortunately, in typical Apple fashion they decided to omit support for DTS pass-through which sends me back to using a Roku 4 for movies.
A good friend of mine has recently switched to using Nvidia shield, but he's into 4k rather than sound quality. I'll probably give it a try, but Google has shown a rather hit and miss approach to Android for TV and since 4k (like 3D before it) falls firmly into "don't care" territory for me, I'm not in a hurry.
Compared to these streaming devices, disc spinners with audiophile credentials look expensive. For the cost of an Oppo 203, you can try an Apple TV4, a Roku 4 and a shield TV for yourself. If you use physical discs, the pendulum swings back towards Oppo.
Good luck, and if you try the different options please report back on what you discover.
