Superuniti, orator 400's and Naim Power Line

There are many options, depending on your budget, how many boxes you want, and what sources you use. The new streamers offer better connectivity at a price, but if you are happy with the SU’s range of streaming functions, there are deals to be had on the old models.

As a step up from the SU, you might consider an NDX with either a Supernait or a pre/power amp. When I sold my SU I went for NDX/282/200DR, which was a big step up. Then there are various 272 options. A good dealer is invaluable in guiding you through the various options.

Remember that as you climb the ladder, setup becomes increasingly important, and you should budget for a decent rack etc. 

You’ve got to kind of consider where you’re going to end up. I went from exactly what you have and crazily fed an NDS into the SU before going for the separate pre amp and selling the SU. Every step is an improvement. 

My current approach with Naim components is NDX > SuperNait 2 > NAC A5 > Ovator S-400 and I am quite happy. 

There is always room for improvement however.........