allow multiple windows of a single app to be sent to a different workspace
Currently (Lumina 0.8.7-devel): if an application has more than one window, then sending that app to a different space requires multiple sends (of individual windows).
It would be nice for a single action to send all windows of an app.
A relatively advanced implementation might have that action within a Mission Control-like interface.
A simpler implementation might involve the grouping Task Manager (all windows of an app as a single icon in a panel). Imagine a menu item, from that icon, to send all windows to a space.