Oddly, I forgot to take this into account when mentioning whether or not I'd join the party.Hell no I wouldn't. After playing XII I figured out it's the Empire with the right motives and more interesting people
The "antagonists" do have far more interesting people on their end of the seesaw, which is only contributory to the motives expressed. Though the actions taken by this 'side' fall under a morally gray category, their goal is undeniably absolute and justifiable. Not so much Vayne's desire to rule as Cid's compulsion to reel the power of their own kind back to themselves; but everything has its flaws. I'd certainly join them with the intent of fighting it out for justice and freedom.