People with different skills and personalities are able to see the big picture. A team (manager) will feel more secure making decisions if the ideas and actions are thought through from all aspects before starting. This will help save time and money, to say nothing of frayed nerves. But I consider the right values even more important. We have to be able to understand without words or explanation what is permitted and what is not!
Key Principle of a Leader #43: A good team has diversity, yet similar values