Would I benefit from a dedicated streamer?

It’s very system dependent. I have two DACs -- Audio Mirror Tubadour III and Luxman DA-06, and both benefit from adding a separate streamer between the DACs and Roon core (SGC SonicTransporter i5). The main benefits are a lower noise floor and a slightly wider and deeper soundstage. The differences are subtle but worth it to me. Having said that, I know many people don’t hear any improvements between the two options.

Of the streamers you mentioned above, I’m also seriously considering the Lumin U1 streamer. I auditioned the Innuous Zenith MK3 (also the mini version), but did not like the sound signature that much. I haven’t had a chance to listen to Auralic G2.1 though. BTW, if you order the Lumin from Upscale Audio they’re offering a 60 day return. That’s a very generous deal if you ask me. Unfortunately, the only way to know for certain is to try it out in your system since there's no clear cut answer.

@arafiq 

Thank you for your response.  That's what I love about audio, no clear cut answers.  Upscale Audio sells both the Lumin and the Auralic.  That 60 day return policy would definitely come in to play.  Thanks for reminding me.  

I'm currently running a Roon Nucleus directly into a Chord Qutest via Curious USB cable.   I'm using an Sbooster Linear Power Supply with the Nucleus (fwiw purchased from Upscale Audio) and found that it made a big difference.  Also currently considering introducing a D/D converter such as a Denafrips Gaia into the chain between the Nucleus and the DAC. 

I have a Roon Nucleus Plus connected to a PS Audio DirectStream DAC and the SQ streaming Qobuz is awesome.

I'm not sure I'd put another device in the path.