Sometime it chooses well, sometimes not. The trick is the hit the suggestion button and then look over what it gave you, and see if you can use that force on the map you're playing on, and complete the mission you've been tasked with. If you aren't happy with it, hit the button again, and it will set something else up. You can hit the button as many times as you like, but always check what it gives you. It will sometimes give you combinations that you'd never think of choosing yourself, and they can complete the task asked. It's a good way to get ideas of force compositions...
