Remove the Name: header for the Generic Collection and replace it with Title:. Add the Message-Id: header to handle the case of incomplete uploads.
This reuses previously defined, though arguably not widely implemented, headers.
Replace Section 5.2.6 with:
5.2.6 Title: Header The POST to a Collection Resource MAY contain a Title: header that indicates the clients suggested name for the resource. The server MAY ignore the Title: header or modify the requested name to suit local conventions. Name = "Name" ":" relative-part The relative-part production is defined in [RFC3986]. Message-Id: Header The POST to a Collection Resource MAY contain a Messsage-Id: header. The value of the header is a unique identifier for the message. The unlimited lifetime of HTTP objects requires that the Message-Id be unique in all time. Any POST to a Collection that contains a Message-Id that has already been used MUST fail and return a status code of 4XX.
Suggest dropping the last sentence. It's great way to deal with P.O.O.R. (Post Over and Over Repeatedly), but I expect most servers will keep a fixed-length list, so I don't think a MUST is appropriate. Better to give a little explanation of how to use it and accept that you'll probably be back in a year or two to write a Draft Standard if APP takes off. --RobertSayre