At the character level we do have things like the Speed Attribute and the Speed Chart (which could be expanded upon), but movement is not even addressed in the combat system! Simply roll for initiative and start whacking at each other. There is a good deal of emphasis on a character's number of Attacks per Melee, which could translate into additional instances of movement, allowing such tactics as flanking, evasion, and re-positioning.
To facilitate mecha combat, a GM could ask a player at the beginning of their turn:
- What mode/formation is your mech in?
- What speed are you moving at?
- What altitude is your mecha at?
- What direction are you heading?
Weapon ranges could also be used to give some idea of the distance between opponents from round to round. For example, if you just fired your Alpha's nose lasers at an Invid Scout, you are within 2,000 feet of the enemy.
On the plus side, I think the Palladium RPG rules system is fairly swift-moving and allows a great range of flexibility. It does require the GM to "fill in the gaps" and make rulings on things that come up during combat ("Okay, I want to do a barrel roll...").