Proposal: Command One

[Father Fletch]

Your take on a variant Science One is one I will steal for my MP games. I agree that the C3I needs of MP are important.
You could also use a modular Science One as a basis for Medical One, Recon One, Logistics One, Agricultural One, MARS One, etc.
Trade out ATVs for FAVs, HAAM Suits, even a towed Commando Scout.
Another thing mentioned in the original rules is that a MARS One wouldn't be operating alone; it would be deployed in conjunction with already active MARS and Recon teams, and act as a mobile base/command post.
If anything, The Landmaster is MORE flexible vehicle to use, and would be more effective than that monster of a beast, MARS One. Otherwise, just deploy a troop of fusion powered M-60s or M-1s if you need Shock and Awe.
MARS One, while cool, is very much a product of when the game was published. IMHO the inclusion of the MARS One in the game is more about game crunch (gamer granola/toys for players) than deeply thought out post apocalyptic need.