Archive - online only, no sync?

Currently using Owncloud in an SME environment.

Would like to be able to move certain (old) folders/files into an "archive" folder so that users retain access via the web interface, but the files do not sync to local clients, i.e. access to files is limited to individual download via the web interface.

Instead of an "archive folder", having a sub-option under the sharing permissions would be ideal: allowed to sync via client.

You can simply disable the sync of certain folders on the client, or you can set up the client to not sync all files on the server, but only certain directories.

It'd be great to be able to steer that from the server (in our case, all shares are created by an "admin" user), rather than from individual owners' clients.

Effectively, I'm thinking of the share menu on the web interface, where options exist for
"USER XXX:
O share
O edit
O create
O change
O delete"

It'd be great to add a control to "view online only vs. allow for access for client sync"