Your horses had just 1 training session. Dependng on rating they will need at least 5 (E/W)-15 (subPar)training sessions before they start to win... and then they level up and need even more training.
Capri Any breed. They dont really have a difference. Some breeds have weaker spots like one breed may not have strong movement in it but another may be weak in speed so it all just depends but really any breed is fine