I am not sure what type of horse Amber is or the story about the situation you have had with her. It can be very frustrating when you don't click with a horse, especially when they are a spooky-type. Some human personalities and some horse personalities just don't mix. Good for you for thinking realistically and doing what is right for both of you.
Now a draft cross is a GREAT fit I am sure! It is comparing apples to oranges sometimes between the draft breed and light breeds. My percheron and draft cross are wonderful. Easy going, willing, not a care in the world. My draft cross is three and has been a joy to train and ride. I am sure you will experience the same type of relaxing joys. Congrats!