Our thoughts leading us to ...

You should try to find a dressage type mare with a small percentage of baroc blood. So a very little bit of pure bred classsical blood, like PRE, Lucitano, Hackney, Friesian, KWPN Tuigpaard or other, but only a small %, so that the majority of blood of the mare consists of any warmblood dressage horse (like Hannoverian, KWPN, Danish, Swedish, etc, etc.)
Than choose a stallion with as much as possible generations full dressage warmblood. The higher his inbreeding level, the more "heterosis" effect will come in following generations.
The chance of inbreeding  problems is most cut down.
Don't just cross with a pure baroc mother and pure dressage father. Unless you want to repeat two more times bringing in warmblood. Seldom breeders have this patience or time.
However you also can breed the revers way by using a recognized stallion with only a very small part of baroc blood and a mare pure dressage warmblood.
The foal will grow out to a typical dressage warmblood once adult.... 
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