Two wins and you are into a semifinal; win that and you're into the final. Effectively, four wins and you are the champions. It's too quick, not easy, just not an extensive enough examination to find the true world's best.
This would be the tournament I'd include Zimbabwe and Bangladesh in to comprise two groups of five, out of which the semifinalists are found. Come the World Cup, then include only the world's top eight teams, who play a full round robin before finding semifinalists.
The ICC has tried to find a way to ensure the World Cup is not left to chance and that is why it has pool stages and super stages before moving into sudden death. That's also why they wanted to include rain days. They end up with a worthy champion but also an exhaustive, convoluted and tiresome tournament that becomes a very poor showpiece.
The Champions Trophy could be the start of the ranking period from which teams begin to try and position themselves in the top eight nations. Granted, finals qualification needs to occur far enough out for commercial reasons but 18 months of meaningful ODI play (including perhaps a quick-fire qualifying tournament involving teams seven through 10 in the world; maybe even teams 10 through 13 have a quick go) to see who gets spot 10 in that tournament. But what this all does is re-energise 50-over cricket and its relevance.
Back to the present day - even with the rain, this tournament has been interesting and its 50-over format so heavily influenced by pitch conditions has made for interesting cricket from close-fought low scorers to close-fought high scorers. Well done, ICC.