Make component workflow outputs optional

We have a few component workflows that return multiple output variables, but we don't always care about all the outputs in every situation. There's a number of built in actions with outputs (Call a Web Service) where the outputs aren't required, and don't need to be defined in order to save/use the action.

It would be nice if the outputs of a component workflow were optional, so that we don't have to create variables to store data we don't always care about?