Reading your post I couldn't help but think we must know very little about what's happening in that spiritual realm. As God's creation with I presume a much different relationship with God yet still able to choose him or to follow Satan. They have free will and wars and they have a so much more vast knowledge of God, at least I would assume. Prophecy would say otherwise, but theoretically, could Satan repent of his pride and then what? What would we be like as people if we didn't have the tempter? If we would still be our own stumbling blocks then what is the impact of Satan on the world? Beyond that, its really baffling what Satan is up to, and why any angels would follow him. Is he just driven by emotions like us? Giving up the long term plan for a little fun with God's people? Also baffling is why God created Satan in the first place, why not make him uglier so he didn't have so much pride? All just curiosities I guess, bottom line is just don't be prideful. What a constant effort it takes though. Also, is there a gazillion greek and hebrew words for pride we are missing? Practically, what is pride? Obviously we have value as God created us, so I would say pride is thinking our value is greater than it actually is. But to be prideful then is to go over the balance of what our value is? Is humility then thinking ourselves as less valuable than we actually are? Is humility the goal or is an accurate reflection of our value the goal?

God controls their fate for good, our too I suppose. The quicker and more fully we surrender and walk this life with Him in the lead, the better we will be.