For advanced workflows it would be nice to be able to specify *combinations* of modifier keys when specifying action modifiers for workflow connections.
For instance, allow an action modifier based on holding down *both* the Option and the Shift key.
(I know there's potential for conflict with global hotkeys, such as Cmd-Opt-Return for the iTunes mini player.)
Currently (Alfred 2.0.3), you're limited to a single modifier key.