If the Catechism isn't the single best, most concise expression of required Catholic doctrine, what else is out there that takes its place?
Don't hold your breath waiting for an answer, although it's a VERY good question.
Just about any pre-VatII catechism is far more concise. As I've written before, there's a reason the CCC is known as the Cataclysm of the Catholic Church. There are some beautiful passages hidden among the general incoherency and excess verbiage, but as a teaching tool I won't let my children be exposed to the CCC. It reads like it was written by a UN subcommittee for the most part.
For English readers I recommend and still use the Baltimore Catechism. I understand what you're saying though, people should be able to trust the CCC... that they can't is an unfortunate and confusing paradox. I file it under "smoke of satan, etc."