...the possibility of winning a championship in a different bracket after losing the first match – in my opinion, is a bad idea.
But in my opinion, it's a great idea. I've always disliked the fact that one loss (even the most ridiculous one) immediately and irrevocably puts an end to tournament aspirations. Because the fact that you need to win all games to win a tournament implies, in addition to undoubtedly high skill, a very significant amount of luck – and that's really not good.