People in positions of power usually strive for more power. The Shapers engage in harsher crackdowns. The Rebels (the Drakons at least) are prepared to unleash doomsday devices. This has all been discussed extensively on this thread.
But there's an alternative in GF4 that's not being discussed....and that's disarmament. Which is the position of the Trakovites.
People have said it's unrealistic since no one wants to give up the power of shaping. But really, only a handful of people hold the power of shaping...those trained in it, and those touched by the Geneforge. This is where the Trakovites have their foothold: the huge majority of the population gains no real benefit from shaping. And those are the people who might be willing to listen.
I like the gist of what Drewry said: "we may be naive, but we want people to believe in the strength of these ideas." Thing is, powerful ideas can change the course of history.
People in this thread have said that no one's going to give up their shaping power...but it was also said, in the past, that people who owned slaves wouldn't give up slavery. Well, times change, and they do so because people hear different ideas, think about them, and, sometimes, change their minds. There will always be resistance to change, and there will always be conflict...but when the dust settles, sometimes you have a established a new way of doing things.