Maybe it's because the first Godzilla movie I ever saw was a late-night presentation of Godzilla Vs. The Thing, but I've always liked Mothra, Mothra works despite so many elements of the creation working against it. For one thing there's no expression possible with the giant insect which just flies from perch to perch using its giant wings to blow things around. The larvae form of the Mothra can shoot out silky fibers to entrap its enemies but they always move so slowly that it's difficult (not unlike the Mummy) to really feel much threatened by them. All that said, the sheer elegance of the creation of Mothra works.
So that made me actually anxious to see Godzilla Vs. Mothra - The Battle For Earth. This project apparently began as a straight up Mothra project but it was decided that Godzilla was a better antagonist for the god-moth.
The story is somewhat convoluted but echoes in many ways the original confrontation between the two monsters from decades before. Godzilla is awakened and later a giant egg is found on a distant island protected by two little girls dubbed the "Cosmos". We get an ancient yarn about there being two moth-gods, Mothra and another named Battra who fought long ago with Mothra coming out on top. Now it appears Battra seems to be on the verge of being revived. Meanwhile a devious business man tries to kidnap the Cosmos and gain control of their power. Mothra and Battra emerge at last and begin to fight when Godzilla pops out of Mount Fuji and the two team up to take on the greater threat. This ends up with Battra's destruction and Godzilla imprisoned again. But now Mothra must take up a prophesied mission for Battra and leaves Earth with the freed Cosmos to confront a deadly meteor headed for Earth in the future.