We are considering ways to implement roll protection so a string of unlucky pulls is less likely, but there is no final plan for that as of yet.
They will be like the Eternal Soul with a pool of powerful characters, including Trooper Eddie. Trooper Eddie, for most people, will be the chase character in their mind (as that's the only character they currently know to be in there), but there are some other really strong units in that soul that will likely gain popularity as well.