For a less expensive option, the Aiyima A07 is quite a good unit, even used with its standard 32v/5a power supply. I have been running mine for about 4 months now and I'm quite impressed with it, compared to my earlier D amps (SMSL SA-50, many DIY 3116 and 3118 builds). No tone controls, though. I use mine with one of the RCA AV switch units so I can plug in multiple sources at one time. To get additional gain and tone controls, you could always combine with a good preamp, I have an older Nikko that I use for this purpose.
That Marantz does look better, from a styling standpoint, than many other of their current offerings.
You may want something a little more up the chain from the A07 for your main system amp, but keep it in mind for secondary systems. It's a good little unit, and the power supply is fine, as are the standard op-amps, IMO.