Here's my idea for how he would work, feel free to ignore or use anything you like!

Two modes - Offense and Defense.

1) Alter Stratagem - Change mode.

Offense:
By Example - weak melee attack that applies a Mark and heal some party stress.
Advance - move an ally forward and give them a Speed buff for one turn.
Command - give an ally an extra action, but also stress them out and Mark them.

Defense:
Retreat - move an ally back and give them a Speed buff for one turn.
Cover Us - grant the first two ranks Riposte.
Stand Your Ground - give party a Move and Stun Resistance and heal some party stress.

Camping:
Only thing I'd change is Eldritch Prayer, I'd instead have something like
Guard Duty - +10 Stress for one ally, -5 for everyone else, prevents ambush. (Would probably make it kind of cheap too).