king indian vs queen indian

Both have tons of theory. The KID I think theory is more required to play the positions well, since the lines are filled with all sorts of strange little moves you won't find unless you study the theory.. sometimes only-moves. So you really need to study the KID day and night, like some people do, to play it at a high level. But the KID I'd say is more complex, so if you do know the theory maybe you have better fighting chances here.

The QID, while it also has tons of theory, can be played somewhat intuitively past a certain point.

Both defenses have specific variations that give them trouble...

The QID pairs well with the nimzo-indian, KID you have to play a pirc. Clearly the nimzo is better, the Pirc just sucks.

So I think I'd recommend QID before KID if you're pairing it with the nimzo.

But really if I'm playing the nimzo I'd prefer to play a vienna along with it.