There were bound to be differences and no matter what we say they won't be changed, a different maker of armor and of course just another opportunity for Disney to have a licensed costume maker supply the costume to the adoring fans, money, money, money.
Personally I would have liked to have seen more of a cross over between clone to stormtrooper, I suppose it can be seen a little with the death and shore trooper helmets.
Hey we could have ended up with Rebels series based TK's, they are the same era