If you had to defense your town and you stand behind your wall and defend-towers, the towers decide itself where to shoot. But wouldn't it be nicer if you self could decide which arger/mage to put into the defens-tower and who to attac?
You should also be able to decide how many of the choosen unit to put in the defens-tower, so the tower wouldn't have always the same damage!!
That would give a bit more dynamic in the fight.
What do you think about that guys??