Mercenary companies are better at defense since they can be deployed to any vulnerable front. The March would take 10+ turns to harden up enough that its not just a target.
Stallions had their first settlement walled and watchtowered in 2 turns, and was deploying war missions on the third. I can't imagine how it could take 10 turns.
But if a March takes deadly damage Divine Stewards goes apeshit
This isn't comparing apples with apples though.
If a march's military gets beat up while deployed offensively, we don't take Divine Stewards (because it doesn't affect our land.)
If a march's military gets beat up on defensive, our land gets smacked and we take Divine Stewards procs.
This same paradigm holds for mercenary companies:
If a merc's military gets beat up while deployed offensively, we don't take Divine Stewards (because it doesn't affect our land.)
If a merc's military gets beat up on defensive, our land gets smacked and we take Divine Stewards procs. Possibly worse than the march because our CORE land is taking a beating instead of march land.
Merc's don't insulate us from divine stewards more than marches do; they insulate us less.
But the most important part is we can afford to lose companies and get nothing more than a new tragedy\drama out of it. We can also pack multiple companies into the same zone to match nomad mobilization speed, recall for the first phase of the Khemetri war only the mercenaries arrived instantly compared to the state army, which got there a phase behind.
Sure, mercs are more mobile and easy to redirect to a new front. So far as packing multiple companies into the same zone, that's what Western Wall and the Stallions did. They supported each other by focusing both of their militaries on the same incursion.
I want an additional march to the north because:
- It provides insulation from losing core, heavily developed land. Defense in depth.
- It will provide a permanent 2-army commitment vs. hard-mode nomads.
- It builds basic infrastructure without costing us actions.
- It exploits resources (iron, etc.) without costing us actions.
- It develops heroic martial leaders, which can really pull us out of a bind.
Of those, only #2 is provided by a merc company.