To date the Formor we have seen in the text remind me more of the gang that couldn't shoot straight, rather than some kind of existential threat. Their confidence is more of the, I haven't been spanked lately, rather than we are here to kick ass and take names. The Reds are gone, the White Court took some serious losses in White Knight and Winter is just now back up to speed after a long period of weakness. And the White Council was put on its heels by the war and internal strife. This equals power vacuum grade 1.
What we have seen is, in a sense, is what happens when you turn the lights off in the kitchen and the roaches come out. Which isn't to say that there aren't Formor who are scarier than the ones we have seen to date. Maybe the Formor we have seen so far are stalking goats sent to test the mettle of the players.