My point is even if you screen them at first you cannot control the quality of what they are posting if you leave them unmoderated or without screening what they are posting first.
My emphasis is not on the content, but on the users.
But judging on how you created the OP you are seriously looking at filtering the users (Invite only) in order to have good quality content. Just like what I said above even if you screened them at first leaving them unmoderated will make their post quality to go down. Your target group is also hard to find and maintain as you are looking for a dedicated and motivated person to keep posting in your website.
And from a technical standpoint I guess it will look more like reddit mashed with facebook than with steemit and medium.
But Steemit is already like Reddit where they have upvotes (which you earn money) and downvotes as well, their subreddits are called tags which is a little bit less organized compared to Reddit.
Switch your attention from content to users. If there are not low quality users there is no low quality content.
If you grow a small base of hq people and encourage them to invite hq people, there will be no low quality people.
As long as there's more good people than bad people, the lq people will be pressured to behave. But at the end of the day there are no good people and bad people, there's people that understand our goal and respect the rules and the one's that don't and will slowly get banned or have to adapt.
The more people understand the goal - the easier to maintain the quality on the platform. Best case scenario you get a self-moderated environment where users vote out bad users so there's no need for staff moderation.
Again, content is not my focus, but the users.
Saying steemit is like reddit because it has upvotes is just like saying youtube is like some porn site because they both have videos. Facebook, twitter, instagram, pretty much all big social media platforms do the same exact thing with minor tweaks and redesigns and yet they still get their share of the market. BUT Facebook is not like twitter just like steemit is not like reddit and just like what I'm trying to do is not like what there already is I guess.