To upgrade, or not to upgrade, that is the question

It's un-possible to recommend anything with this limited information. If you want a path to upgrade, we need to know the system. 

Can you connect a computer in place of your streamer and run some tests?  Link speed, ping . . . 

Ethernet cables improving audio is a debated topic.  IMO, you are already wired, which is much better then wireless and 70 feet is not very far for Ethernet at the audio streaming speeds.  Other will disagree.  If the testing shows a good link speed, I would look at other aspects of your system to upgrade but without knowing more can't comment.  

    I have a Bel Canto E1 streamer running into Hegel H360 integrated, Maggie 3.7's and Velodyne sub DD12.  I am pretty happy the with the SQ,  just wondering if screwing around with internet connections would be worth looking into.  I see once again that there are several opinions on the subject, which is good, that is how we learn things.  Thanks, people,  I will have to try some of your suggestions.

In my experience it’s the last meter or so that makes the difference as my guess it’s using a cable that is insulated/shielded better reducing EM/RFI before getting to the streamer with an improvement in lower noise floor. Simple and affordable test is buy a Supra Cat 8 cable and connect between your 70ft run to your streamer. If the end of your existing run does not go to a wall plate first, being plugged directly to your streamer, then just use a coupling to connect the two cables.