Some Guides.

[Heroine]

Trainer 9
Prize if you defeated him/her: ShinyTryouge

Trainer 17
Prize if you defeated him/her: ShinyTropius

Trainer 26
Prize if you defeated him/her: ShinyMachop.

Trainer 41
Prize if you defeated him/her: Chimchar, Piplup and Turtwig

Trainer 51
Prize if you defeated him/her: Rayquaza

Trainer 53
Prize if you defeated him/her: Darkrai

[Rave]

quite valuable prizes but you'll need to change them when more people become more powerful.