Additional functionality for sliders

I'm working on an application which mainly consists for sliders for parameter control. For better user experience, it would be nice to offer two features: reset to default and fine control.

On VST plugins this is normally done via double-clicks and/or modifier keys. E.g. double-clicking resets the slider to a default (mostly 0), alternatively Ctrl-/Cmd-Klick also does it. For fine control, often Shift-dragging is used. Fine control is useful in cases where the slider covers a large value range with only little screen space.

Is there a way to add such functionality with the existing code via traits or would that require an update to the widgets?