Direct RC delegations are super straightworward, just delegate 50 RC, your account now loses 50 max RC and the user you delegate to has an extra 50 max RC, I say max RC, because RC regenerates, so if the user you delegate to uses the 50 rc, it will come back eventually.

I think you want to do something similar to HP delegations where the receiving account gets not only max RC but current RC, and the delegating account needs to have unused current RC (which is deducted) to make the delegation.

You seemed to imply this when talking about the (important IMO) use case of users needing delegation because they used up all of their RC. This use case wouldn't be handled well if current RC doesn't transfer with the delegation because the receiver would need to wait for RC to charge up.