A friend of mine pointed out to me not long ago, that TV tropes refuses to see Ghetis as a complete monster. I edited the page and the edit was removed not much later.
Here TV Tropes' discription of what a complete monster is.
Complete Monster - Television Tropes & Idioms
As I see it, his actions against N, the B2/W2 protagonist and later his plan to freeze Unova (which will kill many innocents in the process) qualify him for this, even more so after forfaiting the chance to redeem himself not once, but twice. He refuses to listen to reason, especially from N, as he considers him "a human without heart". Ghetsis hasn't shown any remorse for his actions and instead questions himself why his plans failed.
So, I want you to ask you dear Pokemon Community, is Ghetsis a complete monster or not?