I say the delegates should be able to use transaction fees to hire people, take them as profit, or destroy them as dividends, and the shareholders should elect the delegates based on their plans.
Yep. This is what will happen no matter what you want to happen, as delegates are the ones who produce blocks and thus decide which rules they use to produce them.
What are the rules the delegates can choose to aspect or reject?
A delegate can do whatever they like, just like yourself. You can modify the code, rebuild the client, and run it. The only question is whether the rest of the network will accept it.
So if you choose to only accept transactions with a higher than standard fee, you can, because it will still validate.
If you choose to accept a *lower* than standard fee, the rest of the delegates will not validate your block. So you'd need a majority to change.
If a delegate chooses to destroy his income as dividends, the rest of the network will accept it, since it's just a standard transaction.
If a delegate tries to take a higher income for himself (in the case it's not 100% of income already), the rest of the network will reject it, as it won't validate.
Just think about whether the change is a *stricter* or *looser* requirement and that will tell you whether a delegate needs majority approval or not.