RC delegations, yes!
1 month waiting period to vote for witnesses and DHF, yes!!
Concerning your solution to upvote-abuse, I don't understand it fully. Your solution keeps the upvote (renamed to "redirecting a percentage of staking rewards") but eliminates the concept of the reward pool.
Instead of having a reward pool belonging to everyone, and dealing with "reward pool rape accusations", your system allows everyone to own his stake without affecting others.
While this seems fairer and might resolve disputes concerning the use of the reward pool, it's just as if you are getting everyone to constantly upvote themselves 10 times a day (under the current system), and if they want to upvote someone else instead, they have to actively donate.
This will drastically reduce the amount of "donations" people will make. Right now, I want to upvote posts when I see them. Under your proposed system, I'll just keep all the staking rewards for myself.
The reward pool incentivizes voting on other's posts. It is not working well, true, but what's the point of making an account on Hive if no one will give you staking rewards?
I am going to answer myself: Dapps like Splinterlands are the reason. Using custom_json, as you said. Also, social media can still exist, but the incentive will no longer be about earning crypto, but more about censorship resistance on the blockchain level.
I like this vision of the chain, but I am not sure that this is exactly what you meant. Hope you clarify.
Edit - having read your answers to other comments, I think I understand better what you mean. I support this vision of Hive. The current system can be replicated on an SMT if people really want it.