And I would submit that any hypothesis that allows you to claim something has infinite utility (or necessarily more utility than the result of any other action) must itself be infinitely complex, thus infinitely improbable, canceling out the infinity claimed to come from faith.

That's not quite valid— there is some finite program that unfolds Permutation City-style into a universe that allows for infinite computational power, and thus (by some utility functions) infinite utility as the consequence of some actions. It would be wrong for a scientist living in such a universe to reject that hypothesis.