Patience before the explosion is the whole game
(And note that in a highly aggressive deck, often your plan is to make the game end early, which means you're less likely to have the problem of drawing a Falkenrath Gorger on turn ten.) 2
Once Preacher of the Schism's middle ability triggers, it doesn't matter what happens to players' life totals before the ability resolves
At the beginning of each of your postcombat main phases, look at the top X cards of your library, where X is the total amount of life your opponents lost this turn
The upside can be really high, but pre-board this card does next to nothing, and even post-board it could end up being a dead draw, especially since it will never have any impact on the board
For just 3R for a hasty 4/3, it has a saucy trigger