Well, I doubt that's the way he thinks because not all the battles are one-sided.
SLIGHT SPOILERS:
Godzilla gets the tar beat out of him near the end by Gigan, Monster-X, and later Kaiser Ghidorah. Kaiser Ghidorah pretty much defeats him completely for a short time.
END SLIGHT SPOILERS
Whatever the case, the one-sided battles are all grouped together in a sort of marathon of kaiju fights. You always know Godzilla is going to win because obviously he's not going to lose to Kamakuras, Kumonga, or Zilla (Hedorah and Ebirah don't even put up a fight). His one-on-one with Gigan is also far to early in the movie for you to assume he'd lose. The other battle that isn't so one-sided is the Anguiras, Rodan, and King Ceasar battle, though it's not particularly long either.
I think Kitamura simply wanted to pack as many foes for Godzilla as he could into one film, and the only way to dispatch them all within the confines of one movie is to have many short battles. If anything, it probably could be argued that GFW has too many kaiju.
-Anzildrah