Rig looks good... give it a try and see how it turns out. I haven never seen someone animate in 2 parts like that but it looks like it would work.
I guess the only thing you would really have to consentrate on making sure you match the movements of the body to the head latter on.
I am enough of an artist to draw freely upon my imagination, knowledge is limited, imagination encircles the world. (Albert Einstein)
https://www.artstation.com/kurtb