Nerf Shooting Galery with Blaster Safe

My son loves his nerf blasters, so I am building him this nerf target gallery for (insert winter gift giving holiday of choice here). It has a competition tree, 3 shelves of knock-down targets, integrated dart storage, and a blaster safe (cabinet) with a combination lock that he can pick the combo, (and change with my help)

I am building the case out of MDF... I am a professional industrial designer and design furniture with the stuff all the time... it's better for the environment (it is ma