Integrated Amp upgrade path

Yes, MC was a typo.  Really nothing about the Mac I don’t like—just have been very interested in Boulder.

Had not given much thought to upgrading the front end—-kind of in the data is data camp, but admittedly without much knowledge.  Will give that approach a good look.  Any streaming DAC recommendations?

Thanks to both responders!

Can’t comment on Mac vs Boulder, that will likely come down to personal taste, but as for a streamer I recommend the WXC-50 from Yamaha, especially if you listen to a lot of live music which may not be available in hi res formats.  I use Spotify Premium mostly because they only have a handful of live GD Master Tracks on Tidal. Yamaha has a very good “sound enhancer” mode which adds back a little of that air/sparkle compression algo’s lose, and is perfect for Spotify users.  Just make sure you use it in “player” mode and bypass the very mediocre preamp section. 
I’ve also used the Soundnode 2i but slightly preferred the Yamaha and its sound enhancer as a streamer. The Soundnode looks much better and I also liked its app better. It may also be better for android users since it has AptXHD in the event you can’t stream over WiFi or Ethernet. 

Yamaha is not really a good match for the OP’s excellent system. Consider streamers from Lumin, Innuos, Aurender, Sonore, Sotm, etc. 

Also Simaudio Mind Network Player is very good. 

Yamaha’s “not good” for his system?  Care to qualify that statement?  
It’s a digital source, format and features matter more then price.  But go ahead and waste your money, op mentioned that “data is data” so I’m assuming they aren’t a sucker.