Cool idea! I think it is a very innovative way to rank content. It could be added to Steemit too for regular posts. They could keep the "trending" page as-is, and add a new page with posts ranked by RScore.

One small tweak - you may want to set the threshold lower than $1,000. 1k seems like regular users would feel like they have no voice if they had to invest this much to have a say.

How much should the user invest in USD terms to be granted a right to the potential of having 1 RScore point in voting power? $5,000? $10,000? $100,000?

A whole post could be written about this in the context of the current Steem voting algorithm.. I think it is one of the biggest hurdles that is currently holding back investment in SP.