Currently it's not possbile to give more then 2 types of objects to a microflow as parameters from a page. In some use cases more then 2 objects are shown in a page. For example a main dataview, containing a list view which has a listen to dataview, in this case you have 3 types of entities.
For different kinds of functionality it would be great if all three entities could be given to a microflow within the listen to dataview. This prevents making unnecessary extra associations or entities and gives the progammer maximum flexibility.
@Isuma, yes it is needed in complex situations, but Maarten's idea makes building your App in that situation more simple, not more complex. When the need is there, currently you have to add an extra association, just to pass along a parameter value and that is not what an association is for. With Maarten's idea, the extra association is not needed, the domain model is kept more clean and the logic is simpler.
All in all a good idea.
It makes too complex for different purposes within one microflow.