It's a pretty big misconception in my opinion that KID is theory heavy. It's true that KID can be complicated, but at the same time you can play the structure no matter what white does, and you're guaranteed an aggressive game.
Literally white goes for the London System? — get a KID structure. You see 1.g3 2.d4? — KID structure. Even in the mainlines it is all intuitive and you'll play the same 6-7 moves basically ALL the time.
Fischer and Kasparov would run into the saemisch variation against the KID — but up until GM level no one knows how to use it AND rarely anyone plays it.
The grand prix is fun (and you'll know intuitively what to do because you've played the King's gambit before, which is what I've done in the past lol)
You can't post in the forums yet. Play some games!