Where do you go after a BlueSound Node 2i?

I started with the Node 2i then I upgraded my integrated amp to a McIntosh pre-amp with a DAC. 
Then I upgraded my DAC to a Moon D280 with a streamer.  
The Node was good not great. The Bluesound app was great.  The sound detail was improved with each step. 
And when you consider the cost difference it is expected - the Moon is 5 times the cost of the Node 2i and twice the cost of the DAC module from McIntosh. 
Improving the source is an excellent approach.  If your preamp and amp are capable of not ‘coloring’ the output. 
And the most important thing is your enjoyment which could be depended on the interface. I chose to use the Mind2 over the Node 2i as the streamer. 

@cio52 Are you using the internal DAC of the C49?

 If you are then your Node 2i is working purely as a streamer. Your DAC comparison would be from the C49 to the M50.2. 
The M50.2 may also use Bluesound App as the interface. (Which I think is pretty good)

@cio52  sorry for the delay

I don't believe the streamer 'quality' is as important as the 'DAC'.

My rationale is when I upgraded from the Node 2i streamer, I listened to it in 3 configurations.
1.  Node 2i - Streaming and functioning as a DAC
2.  Node 2i - streaming with my McIntosh C2600 functioning as a DAC
3.  Node 2i - streaming with Moon 280 D functioning as a DAC

I noticed an improvement from 1 and 2 on clarity of details in peaks of music.  The use of the Moon as a DAC demonstrated a greater improvement and the overall details throughout the range of peaks and valleys in music.

Additionally, I tested the impact of using the Node to stream versus the Moon and I didn't hear any difference.  I noticed the interface difference.  Therefore I believe the streamer is simply provide source content to the DAC - I'm speaking only from experience as I am not an expert on all DACS.  (I know there are some DACs that require separate clocks)