DAC questions?

I am currently looking to add a DAC to an Acurus ACD-11 CD player and being honest have no ideas as to what I should be looking for? What considerations should I take into account? How much is too little to spend and what becomes too much? Any particular features to look for or stay away from?

I am generally looking for advice to help take the sound to the next level.

I have my eye on a Aragon D2A, but not sure if this is waht is needed?

Thanks in advance for the assistance.

My system can be viewed under budget minded, 'finally complete, not really???'