I like Graboids, but look how much is needed to support them: 4 Stone Pillars and 4 Novas. The only other Earth cards are Plate Armors, which you could power with an Earth Mark alone. Then add more Gravity Pillars and other Gravity cards.
Get rid of the Hammer as Essence said. You might exchange Titan for Pulverizer, which would give you permanent control.
It's hard to win against AI-5 and the False Gods without healing. I haven't played much with the healing cards available to Gravity and Earth, so you will have to test them.