There's no way to know what cards will and will not get banned prior to releasing them. Even with a significant amount of testing groups, you will never see each and every possibility before releasing a set. You only see that when it gets into the hands of millions of players, and even then, that is largely based on the first deck to top at a National or Shonen Jump.
There is also no way to start a card game without the initial cards being broken in some way. What happens is there is only so many things a early card game can do strategically. As the game developers, new effects and strategies have to be developed, and the simplest most basic effects of the early sets become the brokest. Destroy all Monsters. Destroy all your opponent's monsters. Destroy your opponent's Spell and Trap Cards. These cards will stay banned because of the sheer one shot kill they provide. In the old days, they were the only way to do what the game was designed to do. But now with so many other cards, they do what they do better than any other card does, too easily. There's no strategy involved, so the newer more complex cards serve no purpose and are slow by comparison. People only want to see the old cards come off the list, because they are more powerful and get them to a win that much quicker. (And then the game stops being about strategy, but a race to see who can get to their cards quicker)
Making cards more powerful then the Chaos cards will not create balance. That will just tip the scales in the opposite direction. The idea behind balance is that there can't be ione deck type dominating all others. Creating cards more powerful then Chaos will simply create a new CC deck that everyone plays, and Chaos will become forgotten. Anyone remember the CC deck that existed before Invasion of Chaos?
