The biggest issue for me was 'library' mods. ie mods that sole purpose is being used by other mods. SKSE for instance.
They were virtually unable to profit of this system.
However, if Steam handled mods dependy, they could retribute mods like this.
That could actually be very good for AppStore, and free libraries : each sale in the appstore could also profit to the ones that created the basic build block.
