I think it's important not do overdo it, but I think this is an important feature to have.
Not everything we post, has same value. Some thing we we'd love more people to see and it can bring value to people.
Without the ability to pay for reach, it dramatically limits our reach within the 2nd degree network and most great content won't surface.
The way to boost content without paying for it, is through reposts. If I repost what you have posted, my followers might see it (not many of them will), but nobody else. Nobody outside of those following me, will see it. So unless someone I follow, also reposts, and they happen to have followers that I don't (which is not always the case, due to joint interests, joint friends, joint "ecochamber").
There is trending posts which many clients implement, this though simply acts to boost already popular profiles and posts.
Which brings me to an idea of doing trending based upon your own social network, with an "out-reach" toggle that maximizes trending content outside of your immediate following circle.
That's one of potentially many ideas. I think we need to work out some good ideas for reach that is more natural.
