Above statements are true, there is NO WAY to get a specific pattern... you breed and hope you get color period, LOL Some seem to have stronger genes they pass on than others. If you breed a leopard to a non Appy solid mare, you have just cut your chances of getting color in half.
Worry about conformation first- make sure the horse is a good horse. I tell everyone to look at them like they are all plain brown. Look at the horse itself. If it was plain brown, would you still buy it? Is it breeding quality?
And yes, if you can find a fewspot, fewcap or snowcap, of QUALITY, you are in luck, but they seem to be extremely hard to find. However, like it was mentioned above, you have NO control over what pattern you might get, but you will get Appy 99% of the time with a fewspot. Keep in mind also, that the stats that have been compiled on 'color' also includes those just born with characteristics and no coat pattern yet.
In the Minis, I dont know why, but the snowcaps seem to carry an extremly strong roaning gene and all roan out. Never had this with the full size or POA's like what I see in the Minis.
Also I think if you stick with patterns for breeding stock that have a definite spotted pattern- blanket with spots, leopards, near leopards, etc... maybe the roan gene will not be so strong??
Like breeding for pinto coloration.... there is no guarantee at all what type of pattern or how much you will get, LOL