More custom smart list subscriptions

Smart list subscriptions have a plethora of use-cases that could be extremely handy. However, in my experience being confined to the ~3am send daily, weekly etc. only, means that some don't want to use it. Wouldn't adding extra functionality to be able to change this time make it even more versatile? Or even use it as a flow step to send the report on the back of a trigger? Or, if there's X amount of leads added to it, then the smart list gets sent? All this could be practicable via APIs, but I'm sure equally possible with added Marketo features.