its incredibly poorly thought out, approval will work but it needs to be applied in the same distributed way as reports
ie you pick a topic the #tag and then a list of users that approve posts in it
approval being better is a whitelist vs blacklist debate, i currently use my follow list a lot so am liking whitelists but know their pitfalls getting new people in, i have a limited attention so also can only deal with so much
if you want to refine your lists you will need to be adding and removing people, web of trust helps but sometimes you just need to go fishing in global and without some blacklists good luck lol, spam is fucking real