am I missing something?

Good but difficult question to answer. Regardless of your system at any level you can upgrade and get a much better sounding one as long as you are drawn to higher sound quality. You stop when the incremental cost becomes too high.

So, perhaps a suggestion would be to go to some high end audio stores… even if it requires long drives. Or find some local audiogoners and see if their systems motivate you and in what direction.

one of the questions you have to ask is in what direction do you want to take your system… more drive and slam , musical and natural, sound spectacular.

So, what kind of music do you listen to and what kind of sound do you want?

What kind of investment level could you make and what is your venue like?

Also, it would be really helpful to see your system in its venue now. There is a place under your ID to put photos, this is really useful to help us understand your current system and environment. Often great improvements can occur with the equipment you already have.

The sound of this set seems excellent to me

There's your answer.

In fact, I am quite satisfied with the performance of my system. I mainly listen to classical piano, I love Chopin, but also to more modern solo or not very orchestrated piano: Keith Jarret(Runes  and many others), Strelinski, Nevski, Hein Hansen, Olafur Arnad.... also soft jazz, Coltrane,  Miles Davis( ascenseur pour l'échafaud), Duke Ellington.... Autunm leaves album Something Else's....ect. However, reading blogs discussing sound systems of 20k, 50k and more I always wonder if I put so much money into it would I see the difference. This is surely a question that many readers ask themselves....

You have a great system...and yes, if you carefully put together a much more expensive system it can sound quite better...

@marcfrenette - it’s great you find satisfaction in your system, but your question of “better” is a subjective one that can only be answered by you by demoing other gear.  However, you may develop discontentment leading to further purchases.

Check out audio shows like AXPONA and brink n mortar audio stores.

Yes, you could do better of course. I am a piano fan as well, love Keith Jarrett, and I also use the reproduction of piano as a significant means of rating changes in my system. @kennyc has the right recommendation, go hear some of your favorite artists on some different systems, then I think you will have your answer.

I wouldn't change a thing unless I heard other systems that brought more to my life.

Your listening lifestyle contributes a great deal to what is right for you, and you may have it.  The kind of music you like to listen to, what volume, when, how  you listen (in 1 chair or while cooking...) all these matter. 

Not everyone needs or can appreciate a temple to the stereo gods.