Does Islam permit proportional representation, such as classifying Islamic organizations according to their number of members within a larger umbrella organization, so that each category has a certain number of votes?

"There is no harm in organizing and arranging to reach the most probable opinion by representing the group with points. However, it must be noted that representing everyone with equal votes is unjust if they are not equal in trustworthiness, strength, knowledge, or the expertise necessary for the decision. But if they are equal, then counting votes equally would be wise. This is why the 'Ahl al-Hall wal-'Aqd' (people of authority and influence) were the ones who chose the Caliph, not the common folk."