Move then fire - A piece may move 1/2 of it's movement (rounded down) then fire. A unit with a weapon that has a range of 4 or greater may not use that weapon (but may use their standard issue weapon) if they move then fire.
Variable damage - When rolling an attack, if the attacker beats the defender's shield by 2 or more the defender takes 2 energy hits.
Out of ammo - An acquired weapon runs out of ammo and is discarded if a unit uses that weapon and rolls results of the weapons origin less than that weapons strike value during the attack. Standard issue weapons never run out of ammo.
Example: A marine unit fires a plasma rifle it has found. The marine rolls 2 strike dice (for itself) + 3 strike dice for the plasma rifle = 5 strike dice. Because the weapon is covenant, the marine unit must roll at least 2 covenant symbols on it's attack or the weapon will run out of ammo. Let's say the UNSC result with the five dice is 4 UNSC and 1 Covenant symbols. Because the roll included only 1 covenant symbol the gun is now out of ammo and is discarded at the end of the units turn.
Melee - To melee a unit must be adjacent to the attacked unit. No two units may be in the same square at the same time.
In the event of a tie roll both units take one energy hit.
Units carrying weapons that have a range value of 4 or more receive a -1 strike die penalty in melee. A weapon may be discarded by either attacker or defender before any melee dice are rolled.
Fire Teams - Units are divided up into two grouping on each side. Players must alternate each fire team each turn.
Example: At the start of the game the Covenant player decides his two fire teams will be, Team 1 Grunts and Arbiter and Team 2 will be Elites and Brutes. On his first move he moves a unit from team 1 - when his next turn comes he move a unit from team 2. On the next turn he move a unit from team 1 and so on.
If a team loses all its units then the other fire team must split into two groups if possible.
Medic! One marine and one grunt may be designated as a medic. A medic may carry up to three medipacks - each pack takes up one space of the units cargo. If the medic unit is killed, all medipacks are lost.
Effect: A medipack recharges a unit to it's starting energy -1. A unit may only receive one medipack per game. For Example, if Master Chief received a medipack he would recharge up to four energy.
Use: A unit must start a turn next to a medic to receive a medipack. The medic must be the active unit to administer the medipack. A medic may take no other action that turn. A medic may not administer a medipack if it was hit by ranged fire or was in a melee the enemy immediately before.
Medipacks are discarded after use. The medic may discard a medipack at any time to make space for other cargo.
like this idea giving it a try tonight