Your democratic vote system wouldn't work either.
Buy 100 Accounts (only 300 Steem and you don't even "lose" it it's just gone for a while).
Or buy upotes. Ever send like 0.3 to smartsteem? You get like 50 votes.

There is no perfect solution for this.

Also I do not agree with your first point either.
Flags are costly and there is little value in flagging besides going against spam.
You spend 10$ silencing somebody? Well he can just as well spend 10$ to be visible again.
Also it isn't censorship it's still accessible for everyone. (or you would miss most of bernies posts ;) )