You might want to consider an Ayon CD5s. This unit has a tubed dac and preamp output stage; as well as philips professional quality transport. The DAC can handle 24/192 via usb or aes digital in. Its built well; and weighs 50lbs. There are two used units listed now for a bit more than you mentioned was your budget...but in one box you get all of what you seemed to wish for...its a great sounding unit that should get you awfully close to the SQ and flexibility you desire. It also works great direct to amp; so you could possible eliminate a preamp.
good luck.
good luck.