With great risks come great rewards...
Glory-wise that's true for duels and studio fights.
Items- and diamonds-wise that's only true for duels.
Suggestion:
make the studio fights more rewarding.
Have them yield better (epic) items or notes for a studio win.
Diamonds... rather not.
But 30.000 notes or an item of similar value as reward for a studio win...
That's how it is now and it's just being cheap.