Unfortunately down voting is too easily abused by high stake users where they can effectively ban by auto downvote users/accounts they disagree with. Yes, there are many spam accounts that exist, but it is way to easy right now for a high stakes user to downvote everything an account posts, destroying their reputation score, making their account pretty much useless. The alternative score that is based on follows, which isn't based on votes on posts, if it were to become the main score to replace the existing reputation score, I could see as being one way to reduce the abusability of downvotes hitting reputation. Personally, all I'm seeing with the new "free" downvote pool is the potential for a rapid "abuse of commons" for massive downvote campaigns. Think of someone setting up a downvote bot "swarm" by registering lots of accounts...