I doubt upgrading or shortening the USB cable will make a significant difference, the one you have is pretty good. The better clock in the N10 will only benefit you if you use SPDIF, USB connections use the clock in the DAC. I stream a lot of internet radio, and I have found that stations streaming below 320 kbps tend to sound pretty dull. Just for comparison sake, I would try the SPDIF connection between the N100H and the M3 to see if you notice a significant difference. If you stay with USB, a newer streamer might help, but not sure. As for the Ethernet run, I would suggest a very inexpensive tweak, replace it with fiber optics for under $100, and put a short, good quality Ethernet cable as the last link. This made a noticeable difference in my system.
Another Aurender Upgrade Question
The Rig: N100H whose signal feeds into a Bricasti M3. The streamer is connected from my modem with a relatively long (14M) Shunyata Research Venom X ethernet cable. The streamer in turn connects to the DAC with a (2M) DH Labs USB cable which was @ $300 a couple years ago. My setup requires the long ethernet run, but I can get away with a .75 or 1M USB cable.
The Question: I'm looking to improve the sonic qualities of the streamer's signal. It is not horrible by any means but slightly muted compared to the signals from my transport and tuner. To be honest I use the streamer mostly for internet radio from the Conductor App. I flirted with Qobuz for a while but lost interest and interact mostly with the other two front ends. I'm considering one of two options (and only two): Fork a few hundred to upgrade my USB cable (I'm intrigued by the Audience Front Row if I can find one used) or fork a few thousand down the road for a used N10. The internal clock (supposedly) yields a better sonic result with either SPDIF or USB. Or perhaps given the length of the ethernet run it doesn't make a difference. So I welcome comments and ask they be focused on USB upgrade vs used N-10 and with the latter advantages regarding type of connection.