I have the Auralic Aries G2.0 and can certainly recommend you consider the G2.1 based on my experience. I also have an Aurender N100H which the Auralic bests handily as well as a Node 2i (used as a streamer only - not the built in DAC) which isn’t in the same ballpark of the other two. Not incidentally, My personal experience suggests the streamer/server is at least as important as the DAC - and perhaps more so in determining sound quality. Others disagree, but I’m certainly not alone in this viewpoint.
FWIW - I also auditioned the Lumin U1 and mini and felt the Auralic Aries G2 bettered them as well. Regarding Roon and the native apps - I can’t say the Lightning DS (LDS) app is better than Lumin’s (or Aurender) from a function standpoint, but it’s good enough. As far as an interface - Roon is unequalled. But, I dropped my subscription to Roon because I discovered that LDS sounded significantly better than Roon when streaming files, Tidal or Qobuz. For me, the sound quality improvement of LDS over Roon was quite significant. I’m guessing it’s because the native app is able to properly use the buffer built into the Aries G2. YMMV.
Good luck and let us know what you decide.
Best,