Interesting dilemma.
TRL's Sony mod is quite amazing for the price. My experience is with TRL/Sony 595. I assume your model will sound even better. On sonics alone, it will provide much bigger bang for the buck than a music server system for you, since you don't yet have a DAC.
I would recommend getting the TRL mod anyway and slowly building up a music server which is a lot of fun. When you find your favorite DAC, the music server will really sing for you.
TRL's Sony mod is quite amazing for the price. My experience is with TRL/Sony 595. I assume your model will sound even better. On sonics alone, it will provide much bigger bang for the buck than a music server system for you, since you don't yet have a DAC.
I would recommend getting the TRL mod anyway and slowly building up a music server which is a lot of fun. When you find your favorite DAC, the music server will really sing for you.