It looks like right now in your latest Diagnostics I am not seeing very much buffering happening. It looks like there's generally a 2 second pause you're seeing soon after starting watching, but then it appears to proceed smoothly.
I see in the last session you watched, there was one 2 second pause soon before the end of the stream. It does look like your network is generally doing well. One thing I did notice is that you have picked Original quality, which will not allow for the Adaptive Bitrate system to kick in (if you set it to any of the other options, we will reduce the bitrate if needed to continue to buffer properly).
It looks like we may want to increase the amount of buffer we build up when we're buffering to prevent more buffering pauses in the future.
Can you let me know how often you're seeing this buffering per stream? Maybe the instances I'm seeing in the recent logs don't properly capture your experience.