You should stay with the smaller breeds, and to hell with what that trainer thinks. I think tiny people on huge horses look as odd as tall people on ponies. Horses and riders need to compliment each other.
JMO:)
Becky
The QH mare that ride I look fine on. She's in the 15 hand range. That I can do. But I really feel awkward on big horses. They can be really nice to ride, and I've ridden a 16h app who's like riding a couch,and I really like riding her, but when I first start out, I feel like a flea on the back of a dog beacuse she's big and broad. I don't think my trainer's opinion is a negative one really so much as a misunderstood one. She'll figure me out soon enough :-)