This is not a reasonable solution for most people, it requires intimate knowledge of the games you play (which ports they use), a static IP for your console and no more than one player/console per household.

Heaven forbid you have a PC game and a Xbox game that have conflicting ports.

And, I just have to say: you open arbitrary ports to your game console from the internet and talk about security.

Well, NAT itself has pretty much no place on a network these days, so the point is kind of moot...

n>1, not n=1.