I’ve been through a rapid upgrade path since 2019. But over the last 6 months or so I’ve only tinkered with an EE8 and a cable or too.
I’m at that point where I love the sound and I don’t feel anything is lacking. It feels like the scales are beautifully balanced.
As each month passes my urge to upgrade lessens. All of a sudden I’m feeling very cautious about changing anything because it all sounds so right; I’ve become very upgrade (risk) averse. And it feels good.
Am I cured 
Its a temporary feeling. You’ll get over it. 
With an £80,000 system it would be a bit worrying if it didn’t feel good. An ND555 would be nice though.
I’ve not heard enough good things about the the ND555 to convince me…
Plateaus are great, I’ve had a few in the last 20 years. I’m feeling tempted to hop on the NC bandwagon but reluctant to disrupt a good thing and not get on with the new sound.
Maybe I should rephrase that;
I’ve not heard enough good things that an ND555 brings over an NDS…
You forgot to mention the all important “end game” phrase 
Nothing a NAC S1 can’t sort either…
We’re at a great stop point, and really happy with system. It’s what many would consider end game.
Next splurge would involve SF Serafino (dealer recommended), 552 and either 500DR or the 350NCs. That would probably require source upgrade to an NDS555.
Do we want to spend another £30-50k+, even in phases?
Time will tell.
It’s the 500DR spark that has mainly faded. The 500, my last upgrade, did so much. I really don’t want to leave this place.
I’m in exactly the same place. It’s not that I don’t think I could improve the performance of my system by upgrading, say to a better Melco model or a better amp, but rather as you say, I don’t feel anything is lacking.
Of course if I did upgrade then that would probably show me what had been lacking! But as it stands, I’m not aware of anything lacking.
A good place to be. And also a potentially dangerous one, as in my experience changing anything at all when things are so nicely balanced can totally upset the apple cart. One is then comitted to further upgrades to restore the balance that has been lost. This, apart from being very time consuming and frustrating, can also get extremely expensive.
Never was the saying ‘leave well alone’ more apt.
I’m happy to stand with you on this one 
Bluesound Node2 in the bedroom??? At least splurge for the Node X! 
Anytime you have no clear problem with a system but money to spend is a warning sign. Always ask yourself if you want something better or is it just that money is burning a hole in your pocket?
One upgrade of a balanced system always leads to another. The first both elevates but throws the balance off.
I started with Uniti Star and in just a few months decided to upgrade to NDX2 with 500 series pre and amp. Now I feel happy, contented and feel no need to upgrade.
The Uniti Star moved to my bedroom as my 2nd system…now I’m feeling some nagging urge to look at NC boxes to replace the Star 
Racks are fun to play around with. Cables too. For me cables are a rabbit hole, as i always end up back with the Naim supplied ones. “This is the way” have fun that is also the way.
Funnily enough the dealer I use said pretty much the same, not just for Naim kit, when speaking to him at the NW hi-fi show. I’ve only ever tried Mogami (because I wanted flexible) & it was fine but returning to NAC5 was a real improvement. I know this because my wife said so.
This is the way
Agreed. Wondering if my attendance at a get to know the NC 300/350 dealer session in a few weeks time is wise. I am totally happy with my system so I’m not sure what I would be looking for from any change.