I think there could have been more games in the qatr final. Each team should have been allowed to play every team in the apposing table. That way you'd have top 8 teams play every one of each other and the margin of error would drop, too. Right now too much is dependent on a single match. And you get two top teams against each other only one will advance to semis - a tragedy. I would have love to see both Australia and India in the semis.
Only thing is, this way you'd have 16 matches in the qatr final, which is fine by me considering WC comes after four years, but probably for ICC that's too many games and the workload associated with it.