Ability to have different icons depending on states/conditions (i.e., is this place already in favorites or not), and not to have it be tied to the inactive / active state. This would allow for a much-improved ‘favorite’ workflow, which is currently clunky and results in undesirable UX (since you have to use conditional formatting and the buttons can’t be on top of one another).
Ideally you could say - the filled in heart is the ‘inactive’ if this place is in the logged in user’s favorite places, and the outline heart is the ‘inactive’ if it is not.