I would lighten it up with another wash of grey.

You might want to think about losing one of the turret numbers. German tanks only used three numbers. Turn this into 381. Only use dullcoat when you are completely satisfied with everything. Once the Dullcoat goes on you will seal the acrylic wash and lock it in. Up until dullcoat, Windex will strip it to the bare paint.

It is looking better.