I sort of like Team Dream, but they don't have any goal. Think about it:
Team Rocket's ultimate goal is to take over the world with Pokemon.
Team Aqua/Magma's goal is to expand the Earth's water/land.
Team Galactic's goal is to take over the whole Pokemon Universe.
Team Plasma liberates Pokemon (Kind of- I would say more, but some of you haven't gotten that far yet.)
And Team Dream?