Too late to change repertoire?

Hey, all. I'm approximately 2000 OTB, and I've been using the same repertoire since I was 1200. 

 

For White

I play the king's indian attack in nearly 70% of my games. Occasionally, I'll play against a sicilian, where I always aim for the maroczy structure, or a french or carokann, where I go for the exchange variation and it's subsequent lines. Against uncommon's, I just play with my intuition.

 

For Black

Against e4, I play the sicilian. I usually opt for the hedgehog structure if the game goes into an open sicilian. I'm quite comfortable with any mainline sicilian like the Najdorf, dragon or Taimanov. 

 

Against d4, broadly, I play grunfeld with 7. Nc6, in the mainline of the Russian System. I'm comfortable with any mainline or sideline (like the Taimanov, Flohr, Smyslov, Hungarian) of the grunfeld, having studied it for a long time. 

 

 

The problem is, I've been facing a lot of trouble with these openings (particularly with the grunfeld, and against the french) against higher rated players (2000+). Of late, I've considered learning an entirely new opening against d4, like the Nimzo, or the Kings indian defence. A huge problem, I discovered, is that the deep imprint of the openings I already know on my mind, is interfering with my ability to learn more openings. I feel like my mind is already saturated with the openings I know. Do you think it's too late for me to learn a new opening? If not, how would you suggest studying it?

 

Part of the problem is you have no clue what you are doing.

You mention a hedgehog setup and Najdorf in the same breath.  The only time you should be playing a hedgehog setup in the Sicilian is against Maroczy Bind type positions.  Never in the Dragon, nor the Najdorf, and in the Taimanov, it's only in the 5.Nb5/6.c4 lines.

Probably the variation of the Sicilian with the most hedgehogs is the Kan (1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 a6), but even then, it's only in the 5.c4 lines where Black plays a hedgehog.  That setup is too slow against 5.Nc3 or 5.Bd3.

 

In the Grunfeld, if White exchanges, you better be playing c5 before playing Nc6.

 

As White, the Exchange French is nothing for White.  Better to play 3.Nc3 or 3.e5 if you want any advantage.

 

Also, the King's Indian Attack will stunt your chess growth.  Positions are too monotonous.  You need something that is going to lead to different types of positions.  Force yourself to think thru the position rather than playing the same script, which is what the KIA does.  I only play the KIA after 1.e4 c5 2.Nf3 e6 3.d3.

 

Because your issues are across the board, not in just one opening, I suggest you subscribe to ChessPublishing.com. 

If your 2000, your obviously better than me. However, have you ever considered reviewing your games with the help of an opening database? I don't mean to memorize anything but just compare your moves to grandmasters. For me it's very helpful and has helped me round out my repertoire - it helps to stay consistent with the openings you play because it becomes easier to memorize lines as soon as you click on the move and you like; just be sure to know ideas and strategies for your opening as well.
Should you change your repertoire? Well, I mean as black against e4 you don't really have a repertoire - you play all Sicilians and the sicilian is a theory heavy opening.
Back to the question - it's never too late to change a repertoire. If you wish to add an opening then learn it well and play blitz games online with it. It'll always be a rough start(usually) but that's normal.