Well if you kept the shadow, then a cool effect would be where you let go, is where the item drops from the sky and lands where the shadow was. So I learn that it's the shadow is where it will get placed, but then make it the shadow of the item. OR no shadow. Just an idea.
Yes, already talked to our programmer about a tiny shadow over the tile were a tower can get placed (or the shadow of the tower itself, right), good suggestion, thank you.