One of the problems of world ranking is that all continental tournaments have the same weight which is ridiculous. Either both Americas should have one tournament, as well Africa with Asia, or Europe should give twice as many points.
The FIVB ranking system only rewards finishes and not match wins. (Yes, wins mean you should finish better)
But the FIVB does not take into account regional strength. Plus, it does not take into account the strength of your opponent.
In my system I have 2 different levels,within the region (NORCECA Championship, World Champ and Olympic Qualifiers) and then international tournaments. The International tournaments increase the points by 75% and then the rank of your opponent.
With my ranking point system for this year only with the World League and World Championship, Iran would be 5th in points this year. However, because I do take into account results of the last 4 years, they are now 9th after today's win.
They will be ranked higher next year in my system and by the FIVB.