“I want our community to look like it's not only built out of "poor" accounts with hardly any voting power. I hope to be able to build some "dolphins" and "orcas" here.”

This statement sums it up. By delegating through dlease to multiple PH members, PH can have a more distributed rewards base. This diversifies how the rewards are distributed, because people have different interests about different content. And also it inherently builds a middle-class within the community, rather than just a few rich whales divvying up rewards.

And if you're active in the community, you make more money.