This is how I'm writing Robin in my script.
Firstly. Bruce Wayne is a lot more disturbed, and there's a reason why this works in Robin's favour.
In the script, Bruce does not see Dick Grayson as a person so to speak - he see's himself. Since Joe Chill was never found and tried, Batman see's Zucco as his parents murderer, since he see's his younger self in Dick.
Dick is taken to a foster home, where Batman visits him every night. When Zucco's men try to kill Dick, fearing he's the key witness, Batman takes him in.
So initially, Dick is trained so he can become a fighter for when he's older, not as a sidekick.
When Gotham is troubled by Mr. Freeze, Batman concerns himself with him. But Dick wants revenge and thinks Batman is neglecting his parents murder. So he dresses up as Robin, and goes to kill Zucco himself. Never fighting criminals, but using the skills he knows best to infiltrate Zucco's location. Eventually Robin finds him, but cant bring himself to kill him. That answers the question symbolicley "Would Batman kill Joe Chill?" Through Robin not killing his parents murderer, the answer is, no.
I felt if Robin were to be in it, he should have a more important meaning. He is a representation of innocense in Batman's world.
Since
I'm writing Batman as a self-proclaiming 'Man Of Vengeance' in this film, as opposed to Christian Bale's 'Man Of Justice', I felt Dick should be that guiding light.
Cause this Batman has no proper idea of what he's fighting for, and the only way he could answer that question is if he came face to face with Chill...Vengeance or Justice?
In the movie, I have him debating wether he should actually kill Freeze or not, since he has no pity for him (and this is the first time he comes face to face with a Supervillain). But by the end, as Freeze tells his tragic tale - Batman remembers Dick not killing Zucco, and realises not everything in the world is so black and white as he first saw it, he lets Freeze go!
So the events help Batman realise what he truly is. This is then followed by an invitation into the JLA from Superman. Happy Ending