Suggestions for a streamer only (I have a great DAC)

+1 for Innuos Zenith MK3. 

OP, 

Yes, today a top notch streamer is at or above the level of a high end CD player.  In fact my streamer performs at the level of my vinyl rig (also not shabby, see my UserID).

We are taking about full wide and deep soundstage. Instruments suspended I’d space, mid-range bloom, incredible detail with dead quiet background… low noice floor. But with a nearly infinite music library. But like all other pieces of high end audio, you want performance you have to pay. Alternatively you could go the N10 route. About half the price. But given the quality of your DAC you should mate it with something appropriate or streaming will just be a way to find music to then purchase a CD. When you could be experiencing as good or better sound all the time.

Lightning DS is not great but functional for music genres except classical. Roon is better but still not great on listing classical albums. Only Idagio comes close but it is solely classical. On balance there are worse apps than Lightning DS and from my experience not that many better - most are about on par.

I heard Wolf with a T+A DAC today at the Florida Audio expo, sounded pretty good to me!

but at home I have NAD M50.2

Antipodes Audio!!!!!