Ah - here's the last time I had this discussion. No explicit page numbers, but it seems that everyone agrees that you can use TF like the Gift when it comes to learning Divine-backed supernatural abilities. (ie - you can learn the Supernatural ability like a normal Ability, albeit with a minor penalty.)
I'd say that the main abilities you could gain from True Faith are Sense Holy/Unholy, Detect Magic, and Ceremony. You also gain the option of easily absorbing other Divine-backed powers, in the same way that a Gifted individual can more easily learn Magic-backed supernatural Virtues.
I do agree that the actual Holy Magic Power/Methods are a bit pricey, unless you min-max your way around them with Ceremony. ie, only take a single level in each one that you study, thereby allowing you to study a multitude of them (assuming you have Sources for all of them) - and then use Ceremony to boost your skill roll. (Which admittedly does require that you know multiple people with Ceremony, of course.)
Which is the main reason why I tend to go Kabbalah when I do Holy Magi, as they DO have access to Sources for all of the Holy Method/Powers.