Where do I go from here?

What fun to re-discover your prior equipment.

What size room are you going to use them in?

Speaker Concerns, (I never heard them)

Found this about your speakers

https://worldradiohistory.com/hd2/IDX-Audio/Archive-Stereo-Review-IDX/IDX/80s/HiFi-Stereo-Review-1986-06-OCR-Page-0062.pdf

Used for ___ years and boxed for 20 years gives me pause. Is the plastic diaphragm aged in a negative way? I would inspect and then listen before buying other equipment.

Then go from there. 

100 watts is decent power for them. I love my tubes, but 100 wpc tubes is a lot of heat, and the article says the ??? should stay energized?

I have an old pair of ML CLS in my 2nd system.  Great speakers, you may want to use a sub with them especially with a tube amp.  

Yes, streaming is that simple.   You omitted the DAC.  You can get combo streamer/dac systems but they tend to be low end.

Hard wire your streamer to your router (wifi is a fool's errand)

Your DAC is the heart of the digital system.  Some DACs have volume control and since you don't plan to have other inputs, the DAC can replace your preamp.  I use Chord DAVE in this manner.

I use Qobuz, as do a lot of other members here.  Tidal appeals more to the hip hop crowd.

Finally, many of us use Roon to manage our listening pleasure.  Consider that.  If you think you might use Roon, avoid Aurender as they do't work with roon.

Jerry

if you want simple, get something like the Cambridge CXN V2 - streamer, DAC, Digital preamp - get Tidal so you can use Tidal Connect - Qobuz connect still in the long promise stage, forget Roon for now... WiFi is easy or if close to router than ethernet easy too...then when you system is fully going and you are familiar with streaming, then consider upgrade - the CXN V2 holds its value well