Can one ever be "done" in this hobby?

Unreceivedogma I also have stabilized my system over the years in my main audio system
.
SME IV modified tonearm - 30 years
Amp/Pre-Amp/Phono pre-amp - 20 years
Audio Interface SUT - 35 years (maybe a 
Cartridge Benz Ruby - 13 years (time soon for a replacement)
VPI TNT VI+ - 13 years
VPI 19-4 turntable (for 78s) - 38 years
Legacy Focus - 20 years (maybe upgrade in the future)
EAR Acute - 12 years (maybe separate high end DAC in future)
Cabling - I'm a beta tester but only 3 sets of speaker cables in 20 years
Stillpoints - both original and mostly current models when they were first introduced
Synergistic Research HFTs, Fuses and Outlets-when they were first introduced
Shakti Hallographs - 2 pair 15 years
Townsend Seismic Sink - 13 years
Walker Talisman - 13 years
Equipment Stands - 22 years
Omega E- Mats - when they were first introduced
The Gate - future purchase?

Basically, I have maintained most of my components for decades with more recent tweaks adding their abilities.  I used to change equipment more often because I was dissatisfied with the sound but there are many tweaks that I added which could have improved their abilities.   Sure, I'd like a Kronos turntable and $10-$15K cartridge to go along with my 25,000 LPs.   There is also a possible SUT upgrade to the  Zesto Andros Allasso which uses even higher end Jensen transformers and uses them to adjust impedance rather than my using a resistor in my Audio Interface.  

I still have 4,000 LPs and 2,000 78s in storage which I haven't auditioned yet.  I have sold 18,000 LPs & 78s over the last 35 years.  I made up my own criteria for keeping a recording-I have to want to play it 3 times annually (cannot be done in actuality as I have 25,000 LPs, 7,000 78s and 7,000 CDs).  

My cable manufacturing friend has improved his CD playback immensely using his new COS Engineering H1 DAC.  It beats the pants off our very analog (warm) sounding all in one CD players (EAR Acute and highly modified Pioneer DV 05).  It could be that he added immense power supply caps, superior A/C cabling and vibration resistant material to the chassis to allow the dual laser Pioneer to track the CD more accurately.  It beat out a Meridian Ultra DAC in a high end system with an Audio Research CD transport (a recent player).  

My other friend Frank/Oregonpapa has extremely modified the same Pioneer DV-05 with Synergistic Research fuses and PP total contact, omega e-mats and now the gate to also wildly improve his CD sound to high end status.