any suggestions on what to replace Bluesound Node 2i with

I moved to the Innous Zen Mini and Zenith for my networked systems.
I had the Bluesound Node's before. I upgraded my DAC's to Ayre QB-9's, so I needed something that used USB instead of optical.
In any case, I am very satisfied with the changes.
@OP,
Be advised, research what inputs your streamer accepts.
Also, check what software it uses, as some limit what streaming services you can use.(The Bluesound sort of spoiled me with all the apps you could use).
Innuos can use Roon- which I find to be a very fine piece of software.
I tried Aurender, but I never warmed to their software, and it is only limited to Tidal and Qobuz.
Bob

Why not keep the node and upgrade the delivery to it and then upgrade to external DAC.
start with small green computer solutions. They have fiber optic options that clean up the signal to the streamer. Never spend more then you have to. Enjoy the music.

@jjss49 Yes, as my post stated I am looking for a replacement. I find myself listening to Qobuz more through my Control4 Hdmi set up with my Anthem 1120 than using the Bluesound which is connected optically to my Anthem. I did hear the Lumin and was pretty amazed, I just don't want to spend a lot of money without checking other options

When it’s digital it is not hard to make something sound different as desired . So no doubt streamers can sound different for many reasons. Outboard DSP is likely to be able to reproduce similar results.
I think it’s better to say I have never heard bad sound come from a streamer through a good DAC, not that they all sound exactly the same.   

Have you tried a different connection than optical with the Bluesound?   That alone might make a difference.