If I were to say anything at all positive about this film, I'd say that it possibly has the single most effective SFX sequence in the entirety of the post-Biollante Heisei era.
Before you call me crazy, the scene I'm referring to is the underwater fight between Godzilla and the larval Battra, which is one of the few underwater Toho special effects sequences to my memory which, astonishingly, doesn't look as though it were filmed on an obviously dry soundstage (or done entirely in CG). It's dark enough to not look like a set, the screen is constantly awash with hundreds of bubbles, and the copious amounts of smoke and fog for once look absolutely right, just like the explosions of millions of tiny bubbles, as intended. When Godzilla swings Battra around by his tail, the bubbles even shift and swirl tremendously in the opposite direction, and then back again when he slams into the ground, as though the water really were being stirred up by an enormous force passing through or near to it. It's a lovely little detail which is so often overlooked in other films, and it sells the entire thing. It's gorgeous.
And yet, this is the same film which features FX like the shot of smoke and dirt shooting out of the ground as Battra tunnels his way into Nagoya like Bugs Bunny, where the matted-on buildings are semi-transparent and you can see the nozzle of the smoke machine through them
. Go figure.