Anybody gone from ethernet to optical for connection to a streamer?

Yes, optical is a big improvement. Can't say enough good stuff about the Sonore opticalRendu fed from a NAS device in another room. A good power supply for your renderer is also very important to allowing you to hear everything your optical changes will bring. 
Tons of threads on these topics here and on audiophilelifestyle. It's worth doing plenty of research to get a handle on it. Cheers,
Spencer