I'll add my vote to splitting your funds between speakers, DAC and room treatments. Assuming you haven't already invested in room treatments, this make make a big improvement for the dollars invested.
The DAC in the Node is not up to the level of your other gear, and with better speakers it will be even more obvious. There are some great sounding DACs available for a few thousand including some already mentioned. I'm a fan of the Denafrips DACs, but it's worth auditioning other options if you can since there are distinct differences in the way they sound.
The Node is a decent streamer, particularly with an LPS. I think you'd have to spend a fair amount more to get an appreciable improvement and the money is probably better spent on speakers, DAC and room treatments.