What functionality is missing? What is unsatisfying with the current situation?

Currently when you set a pin on a map, when a user zooms in and out the pin size fluctuates and the pin location seems to move slightly on the map. It would be nice if you could set the pins maximum and minimum size relative the the map so that when a user is zoomed out the map is not covered entirely by overly large pins.     

How does this feature request address the current situation?

By being able to set and upper limit to pin size relative to the map the pins would never get so big as to eclipse the map.  

What are other uses for this feature request?

This would also improve the authors control over pin and maps by allowing a minimum size so pins did not get lost. Overall it would just make maps a little nicer to use then they already are.