When I claimed the Fallen were a larger threat, I meant this as "these are one of the only two factions that are currently on Earth at the moment and should they successfully band together, leaving Venus and the moon, they could be a real threat to humanity directly even with smaller numbers."

But are they really a threat? We've killed, going off what we know, a large number of their major players, so an invasion would mostly be trash mobs. Sure they can still do some damage, but I can't imagine they would be much of a threat.

I still stand by saying that it's strange they don't invade full out

What is really strange about their tactics? We went to their tuff to kill the Vex, which ultimately helps them. What do they gain by sending countless troops to kill us when it would be much simpler to just sit back and have us fight the Vex. Best case we kill each other, good case one of us falls and bad case is that we both weaken our forces and they just pick us off. So, what are they suppose to gain by attacking us?

Lose more forces? Weaken their defenses so the Vex could potentially beat them? Waste countless resources on a foe that is happy to fight our enemy for us?

The same goes for Oryx. Speaking in terms of lore, the odds of defeating him is pretty much 0 percent. So it makes sense to send troops to take out the King, since he is distracted with us. It just so happened that we defeated Oryx and the Vex, so the Cabal might actually give us the time of day.

But before this there is literally no advantage to taking out an enemy that essentially cares more about kills your foes than you. It doesn't matter if they have the might, what their forces are doing or any of that, because your whole point is that you don't seem to get that the Cabal have little to gain and plenty to lose by bringing the battle to us.