While this post is literally 3 years old I wanted to pitch in and say that I have a relatively broad repertoire! I really like studying openings which isn't the best at my level, but I don't really care. I play e5 vs e4, nimzo-QGD vs D4, and ruy lopez as white, but I also play kan and najdorf Sicilian, caro kann, and KID (very occasionally) and bogo indian vs 1.d4, while I also experiment with mainline 1.d4 and 1.c4, and evans gambit in blitz. I always think its good to experiment and branch out with openings because it introduces fresh ideas to your chess, regardless of immediate improvement.
I agree with experimenting broadly, but I think the term repertoire implies a strong familiarity, level of knowledge for my skill level, etc. I'm envious that you are comfortable in so many openings--I've tried quite a few (more over the board in casual games or vs. bots than in rated games) like the Vienna, King's Gambit, KID, other modern defenses for Black, but I'm just not comfortable with them.
Guess I need to broaden out my book a little bit!
Openings deniers don't seem to notice how just because you run out of book at some point or your opponent deviates it doesn't suddenly make all your opening study irrelevant. The same themes, motifs, positional play and tactics appear in many openings. If you listen to top players commenting as they're streaming you'll find that after running out of book they'll often say "this is a bit like a position in the c3 sicilian" or a "better version of the tarrasch" or something, and they'll know and understand how to play it. The only thing is you should understand why each move is made, and make sure the author is a good one that can explain it.
My repertoire: white: Evans gambit, fried liver attack, closed Sicilian, caro kann panov attack, french defence tarrasch defence. Black: najdorf Sicilian, nimzo and queens indian, English opening queens indian variation.