As good as the price-value relationship of Bluesound Node 2i is, upgrading to a Lumin U1 Mini made all the difference in my system. So many more layers, holographic soundstage, more details, extended bass.... Particularly appreciated with classical music. Honestly I did not expect this kind of improvement. I did experiment also with different, expensive amps but the increase in SQ was nowhere near the impact of upgrading to the Lumin. You already have an excellent DAC which will complement the Lumin. The return per Dollar of this investment would be much bigger as replacing your other components.
Good luck with your next step, its always a bit of an adventure.
Good luck with your next step, its always a bit of an adventure.