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 upgraded from the Node to the Cambridge CXNv2 and have found it to be a solid upgrade.   I wanted to keep a simple interface across multiple services (similar to BluOS).   Also needed Spotify connect support.  Tried the Moon streamer/DAC and the Cambridge was clearly the best bang for the buck.  (Note: I also took advantage of the balanced analog outputs, so that likely played a factor as well).  
OP here. I am not just looking to replace my streamer. I am doing a major upgrade of my home theater system with a second subwoofer and a separate 3 channel amp to run LCR speakers. I am also replacing my ceiling speakers with much better ones. I am also replacing speaker wire and cables with much better wire. Adding a streamer is part of a comprehensive upgrade. 
Realistically how much of an improvement will a high end streamer make over a Bluesound Node 2i? 
I realized last night that listening to Qobuz with my Node2i was not that much better than listening to Apple Lossless through my Apple TV music app. 
If I buy the Lumin T2 it will cost about 10X what the Bluesound costs. Should I expect a huge improvement in the music for $4500 or will it be more subtle with somewhat better detail, separation of instruments a better soundstage? I am hoping that before I spend the money replacing the Bluesound I will be able to compare the Lumin to the Bluesound on my upgraded system. 
@galleybob you could look for a local Lumin dealer and ask if you could bring your Node 2i over to compare, or to borrow a T2 to try at home. I'm pretty confident you will find the T2 sounds significantly better than the Node 2i. And the T2 is a huge improvement over the D2.
@cat_doorman

Take a look at Cocktail Audio. 
They have from good basic to units that allow two drives (3.5” or 2.5”) that can be arranged as RAID-0 or RAID-1. And it can be a server for such storage.  The one I looked at had CD Ripping also. 
I picked up the basic N25, but the X45D looks cool. A kids display with HDMI out for external monitor/AVR input. A loaded remote control is included. 
Simple access to shares in the LAN. 
While I have a hefty NAS, the 45 can also store a ton-o-music. 
I found a few wrinkles at setup, but once last them, it’s easy to use and sounds good.