I was never keen on towers until I purchased a boat with one and now have a very different learned view, it offers great versatility. I will look for a boat with a tower when I upgrade.
It allows you to get some of the equipment off the floor and into the racks, provides a higher pulling point for beginners, allows those who prefer boards to join in, gets the ropes up and out of the way when there are a few more in the boat and the purpose if just to have some fun out of the course.