BATTLE OF THE UBER-VILLAINS

[Decimator]

[Tomzilla]

[anguirus23]

[Lord Ghidorah]

[Nippon]

[Tomzilla]

[Nippon]

[anguirus23]

[Lord Ghidorah]

Godzilla's ability to hold onto King Ghidorah was rather variable. In the instance you mention, he was able to do so, and Ang hurled himself bodily into KG, repeatedly. That is by no means a minor contribution to the fight, and I do not give Godzilla a solo "drive-off" with Anguirus standing there next to him as the baddies fly away.

Re: Gravity bolt power, they unfortunately seemed to get weaker over time (much like Toho's treatment of KG himself). However, Rodan essentially ignored Godzilla's blasts in GtTHM, but KG's bolts seemed more effective. Several times, KG zapped Rodan and there were the explosions and little flying bits that on MechaGodzilla supposedly signified 'armor being blown through.' Certainly the bolts were strong enough to throw Mothra around, inspire Godzilla and other monsters to avoid them, and throw up constant debris when they struck ground, rock, buildings, etc. etc.
As I've pointed out before, KG's bolts are undoubtedly not the strongest breath weapons in the Tohoverse. However, they're consistently effective across the spectrum of target materials. Density of armor or crystal doesn't matter when the attacking force is gravitic, the same as with non-gravitic force fields.

Still, KG would fly away, so let's continue discussing the winners of the melee.