Advice regarding streaming please.

To be quite definative, it depends.  For many streaming is the primary source. If that is so then I would think the streaming device quality should be conmensurate with downstream equipment.  

+1 daledeee1, based on my having followed threads herein I would optomize the signal going to the streamer prior to upgrading it.  

All this based from one who has streamed only from computer and do little of it. I am considering the purchase of my 1st true streamer. A process I started 8 months ago. I will likely go with a modest but quality one, most likely the recent Node. My next upgrade will likely be a new transport. If I find I streaming to become a major source then I would optomize signal to the streamer.

I own the Audiolab 6000N and I'm very happy with it's build quality, streaming features and sound quality With it's user interface I can control all streaming services (there are many) through the DTS Play-Fi app using my smart phone I do use an external DAC the Exogal Comet Plus, but it does come with respectable internal DAC

Don’t get me wrong, the Audiolab is not a bad streamer, but I know the rest of the gear is capable of better. 

Streamers make a difference.
I used Mac Mini, AURALiC Aries G1 and Lumin U1 Mini. I prefer the sound of the Lumin. Hideous app though so plan on using Roon or Tidal Connect f you stream Tidal or I guess it may be semi usable with an iPad. 
Use a good USB cable (they also make a difference) or a good AES/EBU cable depending on streamer and DAC resolution capabilities. 
 

The streamer is rarely the weakest link. If you are comfortable with the user interface I wouldn't bother changing it. If you're simply looking for something new that's a different story. The Kef R3 are good speakers but could use a subwoofer to fill in the low range or new speakers that extend lower, you'd notice more difference looking there. Get a measurement microphone and REW see about optimizing room treatments or using DSP. Any of those will affect your sound exponentially more than changing a streamer.