Nimzo-Indian Defense

I want to learn the Nimzo for a more varied repertoire, maybe for faster games as the KID is not very practical sometimes.

With black I play the Caro-Kann vs e4 and vs d4, Nimzo and 3..d5 if they avoid the Nimzo.

The Nimzo is always going to be reliable. The opening is flexible and sound, and whenever you get tired of one line it will always be possible to add a new flavor to your positions.

When I switched to the nimzo from the slav, I just picked up one idea against each of the main moves (e3, Nf3, Qc2, etc) and then... play chess

The real main point is that the nimzo itself is incredibly rich, both tactically and positionally, while being objectively equal. Both sides have a wide variety of options to go for, each with their own complexities. Black is able to play for a win in an objectively equal position, this isn't something many openings lines can say they offer.

The nimzo is dynamic enough that generally, the better player wins, even if white does give up some of their objective advantage.

I think the Idea of playing the Nimzo is often being flexible, so you can create positions that match your style. You can play stuff with B6 d6, maybe f5, setups with E5 c5, set ups with D5, the positions can be so different, while in the Qgd you are limited too like two major set ups.

It’s a strong, flexible opening in its own right, where black get developed and castles early, it’s in every grandmasters repertoire for a reason beyond avoiding the exchange.