I think that instead of clearing all of the selected objects, you could only get rid of certain objects you want. Like, let's say you made a temple with a bunch of different objects in it, but you decided you don't want it in your map. Well, you could only get rid of one type of object at a time and you would end up getting rid of other objects around your map that may have also been used in the temple. So instead, you should be able to just keep clicking on the temple objects, so that they would kind of be highlighted, and then press the delete button. This would be better than clicking and deleteing, clicking and deleteting. But the idea of getting rid of all the selected objects could be helpful when you are changeing the seasons and stuffs. XD