Why having a "1 person 1 vote" system? Those who donate more should get a louder voice, that's much fairer.
If you think otherwise you probably have some aversion against money/profit/rich people or any other sort of distorted value that goes against the ideal of free market money which Bitcoin represents.

EDIT: Plus, "1 person 1 vote" systems are more prone to the "public choice problem" described in the following video, since individual members' losses from a bad ruling tend to be too insignificant for them to bother acting against it: https://www.youtube.com/watch?v=mgJ644LPL6g
An organization in which some parties have a higher "share" is less susceptible since these parties would suffer a greater loss from the "distributed cost", so they may be motivated to act.
Not that any of this is of major relevance since this organization is voluntary and people may leave at any moment anyway.