DAC, amp and headphone for the following 5 attributes

Just stepping into the hi-fi space. I am now at the research phase  :)

The main key attributes I want my headphone system to excel at are:

• Detail retrieval
• Instrument separation - like clarity between distinct sounds, which doesn't feel muddied at all. I think this is the most important for me
• Decay - I love those cymbol decays
• Imaging - more important than soundstage
• Black background - like absolutely pitch black

Could you suggest me a DAC, an amp and headphone to excel at those? I prefer a DAC/amp combo device but standalone is also fine.

Price range - DAC/amp collectively under 2500 and headphone under 2000. So collectively ~4000-5000 USD I guess, but I am open to price no bar options as well.