I think to figure out how more activity would play out with the current RC settings one would have to be better a modeling what more use would look like.
I have shared your concern, currently it seems like we have a lot we can do with a little steem, but remember that changes with more users the RC credits get more expensive vs. remaining static.
I don't have any answers, just though I would bring up the point that you can't model it around today's userbase if you want to grow the user base.