I think this helmet really reads well. Not many people attempt the Holiday special from what I've seen so it definitely adds to it's uniqueness. I like that you also did include kill stripes, the ESB yellow ear, and darken the cheeks on the helmet. This was a smart move in that the holiday special helmet doesn't have a lot of detail (most part for being a cartoon, thus needs to be redrawn countless times).
One thing, if you ever decide to tweak it, the blue where there is no damage, looks awfully clean and bright for going towards the realistic look. This could be as easy as just scratching on some detail or painting a light dirt/grey color with a sponge around those areas to give it variance. But this is just being nit-picky.
You should be proud bud! That is one stellar helmet!