IMO, it is personal preference...I haven't had orps of breeding age yet but I do have ameraucana...I have a splash and a black roo. 2 separate pens, but black is good to have if you want to work on projects i.e. lavender. It really depends on what colors you want to personally produce as to what you should keep.
black x black = 100%black
black x blue = 50%black, 50%blue
black x splash = 100%blue
blue x blue = 25%black, 50%blue, 25%splash
blue x splash = 50%blue, 50%splash
splash x splash = 100%splash
you can always keep what you want now, change your mind next year, and either hatch another or acquire another from a breeder with the same quality birds you have . but anyone will tell you that if you only keep one roo be prepared to lose it
murphy's law....
I have been lucky and still have my only blue wheaten ameraucana roo...lost hens but he seems to always make it
you may also need to just choose your best. I haven't hatched any exceptional blue roos(ameraucana) from my shipped eggs, but the splash is awesome which is why I kept him