I believe going by vote count is the best choice for the community.
Vote by value gives whales control over what charity wins. The community in general might feel there vote no longer matters and stop contributing with an upvote.
Having a cast your vote by saying “vote” or using a third party survey I feel opens issues in regards to miscounting votes or third party sites being compromised. Third party survey sites often get trolled by people taking over them by either using a bot network to cast votes, or exploiting a weakness and casting as many votes as they wish.
That is also our current view on the matter. We will see what other users have to say and decide tomorrow what system we will use in the end.