I am an early adopter, picked up 6 Dell DARs back in 2001 (thanks to Jeff Mock and many others making this really work), and LMS (under various names) from 2003 or so.
Now, slowly but surely the DARs are breaking, but I like the platform and I like reasonable quality and passive speakers (none of those powered PC desktop speakers for me).
Headless is fine for me, don't need the remote.

I did buy an AudioCast @ audiocast.io, small, low cost, no amp, quality is only fair.

I am now thinking Pi Zero W, with a good DAC like the miniBoss Zero @ allo.com/sparky/miniboss-rpi-zero.html, and some amp, maybe a TPA3116D2 board with a solid 24v power brick and a DC Buck for 5v for the Pi Zero.

I did a test and put piCorePlayer on a PiZeroW with a Google AIY Voice Bonnet and it was really easy (almost just worked, after a little alsamixer jiggling) using the small onboard amp, or line out to a real amp and speakers.

I did look at the great work done on Squeezelite-ESP32 @ github.com/philippe44/squeezelite-esp32 by philippe_44 and others. But with the Pi Zero, DAC phats, and amps I have a little more choice on both the HW and SW to hack around. If I want a display I can add it. If I want IR remote I can add it, etc.

I think this gets me a full replacement (including case and power brick) for under US$90 (including shipping and tax) with some assembly required.