It would add the objective, indisputable element of an aggregate score. Getting a high score would become an objective: witness IRL game studios that use Metacritic scores as targets. Projects would be incentivized to boost this score with advertising, personal favors, withholding assets and help, and undercutting competitors.
Any ranking is by nature zero-sum. Moving any given campaign up a notch requires taking another down a notch. This is not a zero-sum community; we are all in this together. We don't need a ranking system that splits people.
If you want to have general tiers - 'high quality', 'mid quality', 'low quality', and vote campaigns into that, fine. But nothing more discrete.