Dear Storm:
Yeap...I supposed. Notice that you're far from alone: it happens with lots of musicians. I think that's almost normal, and it have precise causes, specially the fact that the record industry has grown up with this repertory. Even nowadays, the great labels are focused in this repertory. It is reflected directly in the piano life: competitions, recitals, classes, etc. However, by no means I want to say that we should stop playing or listening to these masters: in the very opposite direction, I think that we must know them as much as we can.
Turning to your subject, I think that you can use three "tools" to solve your question (beside listening to chamber, orchestral, etc: it's part of it):
- listen to early music;
- listen to "lesser known" composers of common practice: the term is ridiculous, but it defines what I want to say, e.g., CPE Bach, Hummel, Alkan, MacDowell. Indeed, they're very well known today, but in comparison to Bach or Mozart or Brahms, they are "lesser known". It applies also to "lesser known" works of very well known composers...

- listen to 20th and 21st century music.
And no, don't quit listening to the music you already know. I believe very badly that when someone starts to know deeply the development of our learned music, each audition of every piece come fresh. As an example, if you don't know the german baroque keyboardists (Buxtehude, Froberger, Pachelbel), Bach sounds in a way; after you do know their works, Bach sounds new, because you figure out lots of details, and relations that before were impossible to you. It's just a very simple example: the web itself is huge!
By the way, if you want to, I'll be glad to provide you some suggestions.
Best!
PS: Ginastera is a great composer, and if you are from Argentina, we are near, 'cause I'm from the very south of Brazil.