I'm not sure how long you've been on Medium, but there was a time when The Atlantic and New York Times were posting their articles on Medium. These articles were well read (excellent writers I should add). With a Medium subscription, a reader could get easy access to these two great publications.
Judging from the quality of my feed, I cannot see why a "mostly" reader would want to pay a Medium subscription. Not getting the writers I have chosen to follow is a big turn-off.
Voting for which writers go up a tier is perhaps a bit on the populist side. However, my system allows writers to vote only for other writers in their tier. This should stem a populist rise to the top. When a writer moves up a tier, he/she has to earn the respect of a whole bunch of writers.
Regardless, it would still be a system that everyone understands how it works, which is not what we have now.
Can you imagine where our political system picks leaders at random? . . . . Oh wait a bit . . . . . this sounds like the conservative party in the UK. That's kind of where Medium is at these days in selecting the top writers--from my perspective.