We talked about this before in comments, I think. I'm a big fan of the idea. Coincidentally, @steemcurator01 recently mentioned that they wanted to see more #bursteem100 stuff. ;-)

I used the Open Graph metadata when I was working with SteemJ for #steemlinks. It's really handy if the web site has it configured right. A lot of sites seem to mess it up, though.

I'd love to see this set up as a "sharing service" to really make it flow naturally. I do a lot of link sharing in my RSS reader, so it would be great to be able to also share here with just a click of the "Send To" button.

The big challenge here, I think, is that people aren't going to do a lot of work for 0 author rewards, so it's got to be easy without incentivizing spam. Your idea to have a minimum SP requirement sounds like a good first step.