What's the best non-DAC streamer?

I enjoy and recommend Roon. With that said, the best bang for the buck would be a Small Green Computer sonicTransporter i5, Sonore's optialRendu Lite for Roon only along with SGC's linear power supplies. A Roon lifetime subscription and the above will keep you under $3k.

In order to keep one's dedicated AC line as clean as possible, I'd recommend putting the computer (i5) on a separate AC circuit with the modem/router and run a fiber optic line to the opticalRendu that would reside in your audio system with the DAC. Unlike an ethernet cable, the fiber completely isolates your audio system from the noisy computer/modem/router environment.

None of the other solutions suggested, often at higher cost, offer these advantages.

You can save thousands by buying a small, fanless, NUC with a decent processor including wifi, a small amount of RAM, and a small internal HD for the software. For software you have lots of options. My personal preference is Room Rock, which works great. Of course, a Roon lifetime license will cost you $600, which is more than you'd spend on the computer. The final result would be a high-quality, whole-house streamer for around $1000.

Roon lifetime is $699.

The sonicTransporter i5 is a "small, fanless, NUC with a decent processor including wifi, a small amount of RAM, and a small internal HD for the software."

For the non-DIY hobbyist, it's put together, configured, optimized and with Roon software installed for a couple hundred bucks more.

I realize the OP is asking for something under $3k but, in general, the best streamer cost no object is the Sonore Signature Rendu SE optical. The Innuous and SoTM are cheaper and still sound very good.

But more on topic, I think the best value is the Sonore opticalRendu Lite for Roon. It sounds better than the Innuous and SoTM and is lower cost. It's also the only streamer in that price range with optical networking.

If you go with a Roon server get a NUC with an i5 , 256G M.2 SSD and 8G of ram. It will be about $300 cheaper than the Small Green Computer. Don't worry about assembly and installing ROCK Roons OS a trained Chimp could do it. Just follow the directions.