Delegating stake is selling your vote, a practice frowned on by the earliest users.
The current power elite see nothing wrong with selling their votes to folks willing to pay to play.
You have to decide for you.
If you have less than 500hp, do what you have to do, but after that you should know better, imo.

Htu is what you see displayed on posts.
It is a representation of what you will receive in payout.
It is called htu to distinguish it from hbd because calling it hbd is not accurate.
The difference is inconsequential, mostly.
The main difference is in that the payout will not be all in hbd, so to say that that is hbd on the post would be inaccurate because some of the payout will come in hp and not hbd.
The calculations of which could cause the payout to be less than reflected on the post, but not much.

Mana is vote power.
Resource credits rebuild like mana, but are simply approvals to transact on the chain.
They may have value, at some point.
They have actual value now, but it is very low because the chain has plenty of capacity.
When the games start clogging the blocks we will see the costs to transact in rc's rise.
The redfish will need help to interact.