I don’t think so. A ton of this could be automated. The dev tool already validates most of that, except the duplicate thing. Microsoft already does this. I don’t mind having to follow strict guidelines in package construction (thumbnail sizes, etc.)(don’t get me started on the stupid image layout of the Marketplace, though, you can’t see the ones you want to, and the others can’t be blown up, ridiculous… oh, wait, I said don’t let me get started).
Oh, that’s why I said agreements could be made… Choose a couple platforms, or… just Flightsim.to. Limit the ones from which liveries etc are shared so they can be managed appropriately. Still let other stuff be loaded, but, make it so it’s not sharable.