Right, that's the problem. More general-purpose ecommerce vendors are notoriously cheap and Valve seems to be interested in going the same way, but to actually do a good job of stuff like this you just need butts in seats. You could solve a lot of this with some sane upfront policies -- everything from known pubs gets pre-approved, anything from a curated set of indie bundle vendors gets pre-approved, anything that is already out and performing above X level on console or other PC marketplaces gets a free shot -- and then have a small team of people who both deal with incoming applications and scour gaming media for titles to reach out to. Charge a decent amount for developer-requested review, make sure your staff on this are knowledgeable about the state of the industry, and you could dramatically improve this process without spending too much money doing it -- then leave something like Greenlight in place to catch stragglers.