I am not sure if this is the way it will be or not, but is it possible for an account to give authority to delegate RCs?
For example, I delegate HP to a curation account like @ocdb and grant them the possibility to delegate that portion of my RCs to new onboards.
It might be too complex with undelegations etc...
As far as I remember posting key is required to set (or clear) RC delegation, so yes, it is possible. There were talks about introducing custom authorities that could be tied to specific operations or even types of custom_jsons, so when that is implemented you could allow some service to manage RC delegations for you while not giving it the authority to vote or post in your name.
That would be nice. I have always seen the possibility for there to be liquidity pools of RCs available for apps that could draw upon it. Similarly, there could be LPs for accounts also, where those in need can buy from the pool, distributing the HIVE to providers. These could be paired together also, where buying an account from the pool will also give it adequate RCs - and of course, three could be "hot seat" accounts that apps use where a user can function, but not own the account directly and when they log out and back in, they occupy another seat.
Again, perhaps too much complexity at this point, but thinking ahead for scalability, if there does happen to be millions of new users coming in.