See, the way I look at it, they should have saved the meteor scenario for the true end to the series, if there is ever one......even GFW, they could have had G battle Kaiser Ghidorah, win and in a last ditch effort to destroy our civilization...our planet, they send Gorath and Godzilla destroys it with his beam, and instead of him standing in the ruins, have him just be vaporized....he views Gorath just like any enemy, but in the end the magnitude of the explosion is even too great for him to survive.
You could have some real emotion and closure from the human aspect, to realize that while we spend our time taking the planet for granted and destroy it daily, this creature gave it's life to save it's home, even giving the ultimate sactifice.....but alas, it will not be.
That, and GvD meltdown are the 2 real ways I see him killed off, and they have both been used.