I was thinking also the speaker cable. In the used market you should be able to find a $2k set for $1k, or $1,500 set for $800... as examples. I am very happy with my Harmonic Technology 6N single crystal copper, PRO-9 speaker cables. Purchased used... saved big $$.
I would leave enough room in the budget for an inexpensive tweak like the Synergistic fuse. I used the blue fuse in my CDP outboard power supply and couldn't believe the results for under $200. Another even less expensive increase for me was to pull the lid from my CDP... and add dampening material... very easy and only around $25. The results were similar to the fuse upgrade. Good luck, and enjoy the journey : )
I would leave enough room in the budget for an inexpensive tweak like the Synergistic fuse. I used the blue fuse in my CDP outboard power supply and couldn't believe the results for under $200. Another even less expensive increase for me was to pull the lid from my CDP... and add dampening material... very easy and only around $25. The results were similar to the fuse upgrade. Good luck, and enjoy the journey : )