InnerSphere Medium Laser
Cooldown: 3 seconds
With the current rules it doesn't matter if you fire one ML or 20 ML - three seconds later you can fire them again (assuming you didn't explode by firing 20 ML).
Instead make the cooldown variable on mech heat status - as a simple example "for every heat percentage increase the cooldown time by the same percentage". If mech heat = 0% you get your default cooldown. If at the end of your weapon fire your mech heat = 50% your weapons get 150% cooldown time.
So my HBK-4P laser vomit build (STD250 + 9 DHS):
- If you fire one ML you get 0% heat, so three seconds after the end of the ML burn you can fire it again
- If you fire six ML you get 20% heat, so 3.6 seconds after the end of the ML burns you can fire them again
You can throw in another wrinkle by adding a further cooldown increase depending on current mech speed - If your mech is moving at it's max speed your cooldown is increased.