I agree. Excellent post. I'm not disagreeing with you here, but I had a couple of thoughts when reading this.

1. We need to define verification. In most contexts verification literally means that we know the IDENTITY of the poster. That would seem not to be an appropriate definition given the nature of the medium. It would be more appropriate to say that we want to know if someone is "real." They are not pretending to be someone they are not.
2. If we want to verify that someone is real without really "knowing" the person, then asking those who have personally verified a user to click a button seems confusing and even contradictory. It also seems inherently limiting. I can read any sentence and render a verdict on whether I believe the poster is "real." I could feel comfortable clicking a "Real?" button. I may be WRONG, but I can feel comfortable giving my opinion. The number of actions I must engage in to determine whether someone is "verified" seems to me larger by definition. Maybe I am getting too hung up on the word. But the reason I am focusing on it is because if the word is limiting that creates the problem you referred to achieving the necessary weight threshold to prevent gaming the system.
3. Could an even simpler option be to inform users that they shouldn't upvote any posts which they believe to be from fake or dishonest people? In that case the verification would be baked into their Steem rewards. I agree that it would probably be psychologically beneficial to separate the two. It may be the case that those with lots of Steem power will always be "real," but we are used to seeing distinct indicators which signal authenticity as verified by some independent arbiter.
4. I also agree that some verification/realness option would be valuable to Steem, not just for peace of mind, but for increasing the monetary value of Steem. Imagine, for example, someone wants to create a decentralized dating website but needs a way of demonstrating that users are real. Well they could integrate with Steem and use its verification system. It could be "Trust Powered by Steem." What about a decentralized Uber that wants to make sure its drivers are real? That its passengers are real? Not only would this increase the number of Steem users, it would increase demand for Steem Dollars, theoretically raising its value.