Whether the DDC could help depends a lot on your DAC. It could help, or it could be "redundant" to internal DAC electronics.
I do echo the idea of a streamer though. Not just for POTENTIAL sound improvement but overall function. That is, if you use Tidal or Qobuz and can implement Roon. You get all the benefits of an amazing computer interface through their remote apps and a dedicated server to endpoint connection for the best feed to your DAC.
I've had stability issues with Roon, but it's still worth it to use it.