I just think I need more options for Defensive actions. So far I only have Dodge and Tumble. Actions like parry, disarm, or block are provided per weapon. If you have a shield you can block or shield bash with it. If you have two weapons you can make a parry with one and disarm with the other, or even make a parry with each weapon. The reason for this design is that I have weapons and shields that provide different bonuses to parry and block attempts.
I just need to find a system that fits elegantly with my design and doesn't over complicate things. So far the added touch of realism is making this game a little more complex than I had anticipated.
Can you clarify how the combat/turns works?
As you have a "defensive" move, does your game resolve the turns of each player at the same time?? (frozen synapse)
Then your resource currency is time (ms?), which works not very differently to sunandshadows suggestion.
I also work on a concept for a turn-based MP and i came to the conclusion to use two fixed actions
per turn, too. Managing multiple units as a team should be as intuitive as possible without the player having
to calculate much.
It also depends on the scale of possibilities for the player. Having only a party of 4 can have a more detailed,
complicated system while if the player has a lot of other stuff to do you should dumb it down a little.
BTW: the new XCOM works great with only 1 or 2 actions per unit. It is a shooter, though, and you seem to focus on melee.
Turns are resolved one at a time. However, each unit has a reaction. If a unit is not in range to attack it can "Guard" (like over-watch in XCOM) until a unit moves within range that it can attack. When that happens enemy movement is interrupted and the unit that readied the action can respond (that response is automated).
The focus of my game is both melee and ranged attacks. The melee requirement has made me realize that I need to punish units who flee from melee combat. To this end, I've created a defensive action called "Disengage" that allows you to pull away from someone you are engaged with. It allows you to move away 1 square. You can still move away at your full movement if you don't "disengage" but you risk taking an attack from everyone around you. The other defensive action I have is called "Dodge" it's a passive ability that gives you a bonus to avoid the next attack. Blocking with a shield and parrying with a weapon work the same way. Of course, you can block a missile weapon with your shield, but you can't parry it with your weapon.
So far I've taken sunandshadow's suggestion and I'm currently experimenting with 5 action points per turn. The reason is that most units have at least 2 attack actions per round and they still need to move. Movement costs 1 action point per 2 squares. This means that you can move a total of 6 squares and attack with both weapons, which I think is reasonable. What I really like about this is that if your unit was knocked prone you only have to spend 1 action point to stand back up (a move action) and you can still move a bit more and attack.