There are some good questions there and i don't know how well the actual system will work on the long run. There are just too many minnows and a lot of whales and bid-bots that take the reward pool. What most probably can happen is that people will stop using steemit because the rewards that they are getting are too small and for the future of steemit that is not good. Stake based reward should still be maintained but with other type of calculation, like 50% is based on the amount of SP you're holding and the other 50% in the number of votes you get (altough that is also easy to manipulate).
I'm quite curious to see what will happen with smoke network because they have a different system where they will take into account also other factors like reputation and number of followers and also curation will be 50% and rewards paid in smoke power (they won't have an equivalent of SBD coin).
Yeah, smoke is an interesting one as it is steem 'kinda'. Let's see.