Since she will no longer be a heifer when you breed her I wouldn't be so concerned avout calving ease. I would look at is working on similar breeding in a show contex and Kayr and PCC both run very similar breeding to what your heifer is. Both these operations have good show sucess in the United States and have access to bulls that will power this little cow up since she has all the calving ease she will need. I am thinking Gerrards Pastor, PCC Rome, Rawes Duke, or Rawes Sir T as an outcross to Firwater breeding. This way you can maintain showability, improve powe rand performance along with something unique.
By the way isn't double vision a Zeal son?