There is one thing in @Jompso's post that struck me as true as a buyer: Power Seller status is pretty well meaningless to me. Except for the seller who has < 10 feedback, I pretty much don't care what the status of the seller is. The only thing that matters is "do they have something that interests me at a price I like?"
Having sold less than two dozen things on Ebay in ten plus years, I don't know the ins and outs and benefits of the various Ebay incentives, so do not take this as a seller's advice on what to do. But from my buyer's perspective, Power Seller status is just about worthless.