They believe that perfection is the elimination of weakness, not the refusal to change. If anything, perfection can only be achieved when they can grow, adapt to change, and evolve to become better.
This understanding is what they call the aspect of Evolution. They don't know much about this aspect apart from the fact that it requires the aspect of information and can be enhanced by divinity and their spark of power.
But they are working on it, and when they finally figure it out, it will benefit all of them, not just Legion-8. Even Legion-7 is slated to benefit from their research.
They have found that, apart from the law of order, Cosmic energy and Cosmic Force are also somewhat resistant to Chaos energy too. This is a different resistance to that of the law of Order.