I would look at the WiiM Amp Pro, WiiM Amp, and the Wiim Ultra. The Ultra would need to be paired with your favorite Fosi or other power amp.
All three will give you built in Spotify, Tidal, and a subwoofer output. There's also a $329 streaming unit from Yamaha (R-N303) that I believe has a subwoofer output.
If your budget is higher than $500, there are streaming amplifier offerings from Cambridge Audio, Audiolab, Bluesound, Marantz, Onkyo, and NAD to name a few.
The Vandy's will outclass your lower end Klipsch subwoofer but you may prefer the setup with the subwoofer in as it may give you a bit more punch to the low end.