When I think of GMK I think of Godzilla with no pupils/iris and Mr. Burns's neck. Basically what you got going.

I'm getting a bit of a Super Godzilla vibe with the "spikes" on the arms and what looks like a crest on the head.

Reminds me a bit of The Godzilla Comic when Godzilla appeared to take on a "transformed state" while fighting Gandora.

It looks good at least

Hmm

Looks like biolante x Godzilla