Campaign-wise, I'm looking at the below rough outline for a week or so of action. The majority of the Militia is defending various fixed targets around the planet, and the Ghosts' orbital forces spend some of their time knocking down Militia satellites.
1) First Contact: Elements of the militia's Recon Company try to get close enough to ID what the Ghost Regiment has brought. Only the Recon Lance of the Hover Company has any hope of catching them, but the other elements might be able to provide some blocking/channeling assistance, while a pair of Aerospace fighters make a run at the VTOLs before going bingo and having to return to space. Victory for the Militia is LOS to the DropShips. Victory for the Ghost Regiment is annihilation of the Recon Company's element. Some kind of morale rule will be necessary to determine when the Ferrets bug out. Who wins will determine how much reinforcement the mine head in the next mission receives.
2) Probing: The Maneuver Lance of the Ghost Regiment 'mech company and the Transport Lance of the vehicle company raid a mine head, trying to grab some gold. One company of Militia Mechanized Infantry is on guard duty, and is reinforced by either one or two Air Assault Battalion companies with one or two Attack Lances of Warriors (one if the Ghost Regiment won the last scenario, two if the Militia won). The aerospace element can provide two passes to the Ghost Regiment in this scenario, one or two turns apart before they have to return to space for gas. Victory points for the Ghost Regiment are determined by how much gold they make off with. Victory for the Militia is destruction of any Ghost Regiment 'mechs and vehicles. Killing their infantry just slows downs how much gold they can load. Victory here determines what units are available in the next scenario.
*Repair Cycle*
3) Brass Tacks: The full company of the Ghost Regiment 'mech company (or what's left of it after a repair cycle) hits the Screaming Eagle hangar (the empty one). This is a trap laid by the Militia. Victory points for the Ghost Regiment are determined by how many 'mechs they get off the board AFTER they've determined the hangar is empty. Victory points for the Militia are determined by how many 'mechs they take down. Militia forces available for this mission are a full Battalion with Artillery support, plus one Hover Company, and whatever survived the last mission to "close the door" once the Ghost Regiment has gotten a unit inside the hangar. The Ghost Regiment will schedule the attack to maximize availability of CAS from the Aerospace element, giving them a pass every other turn for five passes total.
4) Smash and Grab: While the 'mechs are hitting the Screaming Eagles' hangar, the Hover Company (and attached surviving infantry) try to knock over a platinum warehouse. Initial defenders are the corporate security force, reinforced by the Jump Company from the Militia Air Assault Battalion after 6 turns. 6 turns after that, a Hover Mechanized Infantry Company arrives. As before, Ghost Regiment victory points are determined by how much gold they make off with. Victory points for the Militia are based on casualties inflicted on the Ghosts.
*Repair Cycle*
5) Showdown: Having determined the hard way that their main targets are at the First Ceti Hussar hangar, the Ghost Regiment throws it's remaining forces at it in an attempt to cause as much destruction as possible. All surviving Ghost Regiment forces are available for this mission, plus CAS every other turn. The Militia will defend with the damaged 'mechs in the hangar, plus a full Battalion of Mechanized Infantry with Artillery Battery support and a Hover Company flanking the Ghost Regiment force on turn 6. Victory points for the Ghosts are determined by enemy 'mechs destroyed plus number of Ghost units that make it off the board. Militia victory points are based on Ghost units destroyed.
6) Retreat: The surviving Ghosts are chased by the surviving Militia Hover units. After 12 turns, the second Hover Company arrives to reinforce. Artillery support is available to the Militia for the first 12 turns, and CAS is sparse for the Ghosts (only 4 sorties... the aerospace units are preparing to defend the drop zone). Rolling map sheets will be used. Victory points for both are based on how many Ghost units escape. The Militia forces break off when their morale fails.
7) Counterattack: The surviving Warrior VTOLs mount an attack on the drop zone while the Ghosts are at the Hussar hangar. Defending units are the dropships and Field Artillery section. They have Flak ammunition, but need three turns to get it from the Dropship. All CAS is supporting the attack on the Hussar hangar. The Militia gains a victory point for every 10 points of damage inflicted on the Droships, plus 5 for each Field Artillery unit destroyed. The Ghosts gain a victory point for each VTOL destroyed. The Militia forces withdraw when their morale breaks or they run out of AC/2 ammunition.
After all that, the Ghosts withdraw off world, having received word that the 1st Ceti Hussars are withdrawing from Misery, and the beaten Screaming Eagles are inbound from Elidere IV.