@nathanmars, Recently I've crossed the 500 SP and I've never invested in the Steem, just Powered Up my 50 to 60% of my rewards and i will continue to do that, and in my opinion at this point of time i have to grow my account to more extent to think about the effective Delegations.
And for sure Delegations are really effective aspects in the Steem Economy and we can do that with many subjects, means, to earn interest, to earn passive income, to support particular individual or community and to support projects.
And in my opinion, when we stay inactive in an economy then, Steem Power should be delegated because in that way that Steem Power can be used for the good things and inturn people can get passive income or interests.
And we can watch, some Steemians help others by delegating because they saw value in their work and to give some growth they delegate them so that they can use that SP effectively.
Wishing you an great day and stay blessed. 🙂