How about slowing down shield recharge rate instead of cooling lasers quicker?
Or something like the Fuel Tank OXP, you have a cylinder of coolant strapped to one of the missile pylons, which when activated pumps a massive amount of coolant around the laser (only to one you are presently viewing) to bring the temp down. The down side of this obviously is that it takes up precious missile pylons and is single-use.
One could imagine all kinds of power-up devices; a one-use compressed-gas cooling tank for lasers or cabin temperature, a burn-out energy/shield restorer, even a super laser that burns out after one use (like on 'doc' Smith's Dauntless in the Lensman books).
I can see good reasons for limiting equipment to avoid too much complexity. I prefer to use the "semi-cheat" of saving at every station.
