Are all cirstances of a child's life taken into consideration for custody or just food, clothing, shelter.?

My stepson live in NY.. his father lives in MT. my stepson is ten and sleeps in bed with his mother because she cannot move out of her parent's house and be financially stable and there is nowhere else for him to sleep. In MT he has his own room. my stepson goes to a private school where they don't have a playground or a recess. In MT he can walk to school, has recess and participates in several activities with other children. my stepson also goes to school and after-school from 8am to 6pm. In MT he would come right home after school. my stepson is overweight and out of shape due to lack of exercise (he rarely ventures outside of the home and school). In MT he rides his bike every day and loses tons of weight every summer due to exercise alone. there are so many other ways my stepson benefits by being here. NY family courts are extremely gender bias. would we have a chance based on the extraordinary number of benefits to him relocating to MT with his father? or is it pointless to try?