I think the NAPs (official and unofficial/oorp) that the Corsair and Outcasts factions have made with other factions are also what's killed them. They've shut themselves off from potential targets and things to shoot. Outcasts are in really good proximity for consistent raids against Order which could really boost the activity of both factions, yet they currently have a NAP. I can't help but feel that the system design choices that lead to both those regions of space being more connected were not done with a NAP in mind.
I think it'd do both factions some good if they start including some variety in their raid options or visit places they don't usually go to, and try to build up their activity from that. Furthermore, more activity in the Taus and Omegas would hopefully encourage more Outcasts and Corsairs respectively, as those regions are dead af.