any suggestions on what to replace Bluesound Node 2i with


I am doing a major upgrade on my home theater system. I want to upgrade my streamer. I can spend around $4500 if I have to. My dealer played a Lumin T2 and the music, Tidal, sounded amazing. He said I would be okay with the D2 if I wanted to save money
Any one have any experience with the the Lumin's. I am open to other streamers, it does not have to be Lumin. Thanks 
galleybob
I’d be looking for a player better than BluOS. Many are.
+1 on the Ras Pi4 with piCore player.
Toslink isn't necessarily awful. With good glass it's better than coax with a middling cable.
You don't need to spend a lot for a good streamer. The Cambridge Audio Cxn v2 is a great streamer and also uses the Wolfson chips in it's Dac. Sounds great looks great and a bargain at $1099. It's also Roon ready.
I find Bluesound to be not as good as Control4 streaming to my Anthem. I am also thinking that Apple Lossless even though it is 12/44 is sounding better than Bluesound
Bluesound Node 2i is optical. I have tried it with RCA, and Coaxial. My best results by far have been optical. I find that HDMI has been better so that's why I am not using Bluesound. To be fair when I tested coaxial I used a $30 cable, I'm sure I would have had better results with a higher quality coaxial. The optical cable is the one that came with the Bluesound
I am doing a major upgrade on system so I am looking for a major upgrade to streaming. I stream Qobuz but now I also stream Apple Lossless
As a happy T2 user I would recommend the Lumin T2 especially if you are coming from a Bluesound 2i. Prior to the T2 I had the 2i. Tried using its internal DAC but was crap and then had it go into the Mytek Brooklyn Dac+. It was decent but nothing great.

SQ-wise the T2 sounds spectacular. The weakest part is the Lumin app but since I use Roon I have no need to touch the app except for the initial setup. 
This iFi Zen Stream unit just came out.  I have one and am happy with it so far.  It works with everything I can throw at it and incorporates their other technology into S/PDIF, USB, and power supply. I have an external USB drive plugged into it and it uses Volumio as the interface for playing those files. This is designed to output to an external DAC and does not have analog outs, which is perfect - I didn't want to pay for that. I wanted something dedicated for getting internet content and local files to my DAC and that's exactly what it does. 

https://ifi-audio.com/products/zen-stream/