Leo loves to fight, he was dropped on his head as a kid, he has a signature beam attack, he has a time travel plot, and he gets a new transformation every movie
he's literally Goku
And it's Ghidorah who was called "King of Terror" here (after a Nostradamus prophecy for 1999).
Under the armor Leo became "Eternal Mothra" neatly solving the issue of Leo's successor. I think I like the third movie the best. It's a strange trilogy but full of ideas.