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29%
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14%
Yea, I don't really think he was supposed to be stronger than the LT there, just that what Galactus was doing did warrant the LT's attention. They sent an attack that would've felled him for sure were it not for Reed Richard's meddling.
He was evolving to a different stage, beyond the sum of the aforementioned parts. The Galaxy eating was a simple test of a technique that allowed for far more large-scale feeding, the final stage of which would involved eating the universe.
In the end he did not make it to the stage he intended to (as he was prevented from eating the final components), but he did merge with Surfer and change the Power Cosmic to the Power Essential, and no longer had need to feed ever again. That's what the failed version of his evolution resulted in- eternal release from the hunger and an upgrade to the very nature of the power cosmic.