So there are four types of action: Attack, Defend, Move, and Command. I'm inclined to set the basic cost of mirror matches as even, so 2. So Attack action played against another Attack Action means both Titans must pay a minimum of two cards to make successful actions. This minimum may be modified for the adjusted cost, either increased by two points or reduced by two points. That covers twenty outcomes, distributed evenly across 31, 32, 30, 21, 20, and backward.
That's right, if the player with the Initiative plays an Attack, the player without the Initiative may play an action intended purely to make that first action less likely to succeed. Right now I'm working with a crew score of 5 for five cards per hand maximum and a particular refresh rate, the rate at which the player draws cards from her strategy deck. About to get shot in the face? Defend! Find them Defending? Use the respite to utter a Command. Where they Command? Move into position. Should they Move, Attack! Or seize the Initiative and Defend when they're in position to Attack, Attack where they pause to Command, Move when they must Defend, and Command when they attack - Commands can unlock Battlefield conditions and models by Tactical Insight, change Objectives by Strategic Insight, conduct Damage Control, and make Heroic Declamations (Bad Ass Boasts) to seize the initiative (rather than bidding as previously).
I think Battlefield decks and Objective decks should be built alongside Strategy and Titan decks. Buildings and weather conditions should come on Command, after all. Plus it means that both players can contribute to the Battlefield deck. Objectives are owned like Titan decks are.
Objectives include: Lightly Damage, Heavily Damage, or Destroy the Opposing Titan's (Insert System Here, flashy name), Exit the board, Lightly Damage, Heavily Damage, or Destroy a Battlefield (terrain) model. Hold the line: survive x number of turns from objective in play.
Battlefield cards include terrain, given a single damage track like a Titan card telling you its profile at Undamaged, Light Damage, and Heavy Damage. Destroy results in the card being discarded, Overkill results in light damage to adjacent Battlefield models. Battlefield cards also include conditions, like Sensor Disruptions, Gravity Fluctuation, Liquifaction, Earthquake, Electrical Disturbance, Hurricane, Electro-Magnetic Pulse, Orbital Bombardment, Solar Flare, Caustic Rain, Sandstorm, etc. These would all give various combinations of effects, such as increasing Traction of all Battlefield terrain, inflicting Light, Damage, Heavy Damage, and Overkill Damage (Orbital Bombardment), increasing Signature, disrupting Shields, causing misfires, and so on. What's a misfire? When engaging in a Fire Weapon action, and failing to be successful in Caustic Rain. Electrical Disturbance: Lose a Target, and so on. Maybe your plan is to engage in a Sandstorm where the enemy Sensors won't spot you until you're right on top, or maybe have your own advance stalled by an Earthquake.
Which brings me to the notion of Open Terrain cards, which replace other terrain models when those models are destroyed. They're the cheapest cards, and if each terrain model is based on 6"x6" bases, at minimum each player contributes 8 terrain cards, and 16 get played. Three players? The deck is at least 24 terrain cards in that case.
Speaking of which, I've decided on close combat weapons: They have a Fire Weapon profile, like a shooting weapon. Both shooting and close combat weapons can be used to punch, although close combat weapons will probably be better armoured on the whole, but the shooting profile is Rng0". So a Titan can punch an enemy Titan as it passes by in its movement, or may move into base contact and Fire Weapon any armed close combat weapon at a Target in the weapon's Orientation.
Power Fist Arm3 Rng0" Mun1 RoF1 AoE1 Pw4
Chain Fist Arm3 Rng0" Mun1:2 RoF2 AoE2 Pw3
Laser Burner Arm2 Rng0" Mun2:1 RoF1 AoE3 Pw4
Ram/Trident Arm4 Rng0" Mun1 RoF RoF1 AoE1 Pw3
The Trident is indeed the best punching device. Others are better for aimed attacks depending on how you can be crush, slice, or burn. Doesn't do the same overkill though, which is preferable to merely ablating one of the enemy's weapons. By contrast, aimed shots by the Laser Burner will be cataclysmic if they can be pulled off.
Titans continue to move at a set speed, slowed by Battlefield terrain models having greater Traction than the Titan's Propulsion System, and in the same direction, arc of turn reduced by the same. So Titans move forward at their current speed each turn after actions have been determined successful or not, and then they defend, attack, or command. Except when they seize Initiative, then a Titan get to act twice in a row. Ties favour the player with the Initiative.
Cards are worth three states: Undamaged, Lightly Damaged, Heavily Damaged. Battlefield conditions will have corresponding severity. Easy missions will be likewise expensive. The harder the mission, the more resources in actions, Titan, and terrain the player can invest.