While it would make it much easier for the coop managers, it wouldn't save much in the way of money which is the primary reason for the coops to begin with. I do believe that there should be SOME coops like this, especially for new coop managers to get their feet wet and make sure that they both have the time and are up to the task for the full coops. This would also give many of the members of the site to get a taste of what is involved in sorting a coop when they get their big box of parts from Mouser and have to both wait for backorders and sort the parts for the kits that they are getting ready to build. And then keep in mind that this is only a small part of the work that the coop manager has to do.
These partial coops should be for more than just the board. They should include the parts that are not ordered from Mouser such as the Heat sinks for the express, the cases for the dongle, the connectors used on the smart string controllers, ect. This will both make it easier for the members to complete the kits as well as cut the time and expence for the coop managers running the coops.