Regarding the originator’s question about separates, I primarily use a McIntosh C2300 (the last, all-analog, tube preamp; I don’t listen to digital files, and wouldn’t want a built-in DAC if I did!), coupled to a McIntosh MC402 amplifier. Although the MC402 is a solid-state amp, it uses Autoformers whose output impedance is similar to a tube amplifier. I have this pair coupled to a pair of B&W Matrix 801 Series III loudspeakers. This combination provides tight, solid bass and warmer mids and highs, Great sound!
Previously, I used a Sunfire Classic Vacuum Tube Control Center (tube preamp) with Sunfire 300 amplifier, coupled to Innersound Isis loudspeakers, so I definitely prefer the tube/solid-state combination. I still own the Sunfire tube preamp (sounds so good I couldn't get rid of it), and occasionally pair it up with various other (solid-state) amplifiers I still own to listen to for a change!
Go with separates, it gives you more flexibility and options.