External DAC?

Yes, DAC's matter and you can improve the sound to your liking with proper selection. Some will give you a wider more open soundstage, some will tame harsh recordings, some will sound different, but not necessarily better. I would search this site for DAC reviews and conversations to help narrow the field. And since you are considering more musicality and less fatigue, you may want to look at R2R DAC's like MHDT Orchid and Audio Mirror Tubadour as well as many more.  Pick a few based on user reviews, then buy used.

You are not loosing anything by using the Node as a streamer only, you are opening up new and possibly better sound. 

Good Luck!

Me thinks you zigged when you should have zagged. I had to look twice to make sure I wasn’t in the digital forum.

Better sound put a decent LPS to your router setup, a quality Ethernet hub with LPS like the SW8 or others to add a LPS power supply , good quality Ethernet cables ,as well as USB cable a big step up  in streaming sonics. 
I added a synergistic purple to these which also added to the fidelity.

bettering your Audio system , also cost  more $$ . Removing all weak links 

in the chain.

I've found that fitting a 12v DC board from PD Creative, so there's no AC in the Bluesound, is well worth the exercise.

A Topping D90SE Desktop USB DAC with a high quality USB cable makes a difference.

Moose99. You have two exact same threads going at the same, WTF