I managed to find three terminals on my first playthrough.
In order, as near as I can make of it:
Palmer has a grand total of fifteen minutes of actual screen time (if that) and barely more than that in mission giving your orders. She really doesn't have time to be developed as a character. Lasky got the lion's share of his character development in the live action Forward Unto Dawn webseries.
The Lich didn't slag the tires, it disabled the gun, and the Mammoth backed the **** up to avoid getting toasted ther est of the way. Or possibly the Lich couldn't destroy the Mammoth, just disable it. Think Plasma Pistol, but "**** you" size.
I personally liked the Mantis. It's Mjolnir armor XXXL size.
John is good at everything related to combat. Seriously, that's why he exists. He can drive scorpions, warthogs, mongeese, ghosts, wraiths, specters, choppers, prowlers, revenants, and can pilot falcons, hornets, banshees, longswords (end of Halo:CE), and obviously Broadswords.