What it doesn't do using 2014 as a comparator is unfairly reject from nomination right-wing US work. Possibly it favours US liberal/other over non-US, more than it favours US right wing over non-US : but you'd need actual work to test this.
Now compare the sad, and rabid puppy slates (now I'm willing to be corrected about Kloos, because he withdrew and I'm reading his trilogy at the moment and while its military-knows-best MiltSF 1 1/2 books in, maybe there's going to be an entirely justified marxist uprising against the useless Government in book 3, and we never actually (so far) see the SinoRussians so maybe they're capitalist oligarchs, but their slates are either all 5 nominations from right wingers, or 4 right wingers and a not obviously non-right wing Military SF writer.)
The effect of the slate(s) was to produce a set of nominees more unfair (against the populations, books, published, sf published, english-language translated data) than the 2014 nominees that the puppies felt were so bad they had to make an extra effort in 2015.
Only the fact that (Kloos) withdrew, let back in a nominee not from the US.
I think the only rule change the World-con needs is a guaranteed non-US slot out of the 5. It need not harm the puppies after all they can always block vote Vox Day.