@OP: I fully agree. People are too used to just run through every obstacle, yet no one complains it doesn't work like that irl. Yes it's a game, yes it has elements that are unrealistic, but 2 objects in one place are not unrealistic but impossible.

Full collision detection has potential problems because of people blocking the way (there are ways around this too), but partial collision detection should definitely be implemented (at least player vs hostile). It makes much more strategy possible, like tanks actually protecting the magi behind them.