I like to attack enemy cities with a group of over a dozen artillery or cannons in one stack. It sure does take an unecessarily long amount time to do this.
I know some of you might say to use an army but that is very limited.
I wish there was a way where I could just right click on the stack and instead of just being able to pick one unit to wake or activate, you could either hit "shift" or drag the mouse down the list and choose the entire stack to move at once.