Just posting a few ramblings about the way the dilithium crystals and phaser banks worked in TOS that I noticed.
It would seem that there are four phaser banks that feed the various phaser emitters on the ship but no pair of emitters can pump out all four charged banks simultaneously. In "The Paradise Syndrome" a phaser bank discharging fires a pair of full power phaser beams but the other three banks are still ready to go. Presumably then if the ship was surrounded it could simultaneously fire 4 pairs of phasers. As each bank is discharged they would be recharged at a rate determined by what power is available.
The dilithium crystals being the main power source actually is very clever because it is pretty much "magic"
They could store colossal amounts of energy (maybe
even increase the amount you put in
) that would be available for immediate use to energise other systems. This could free the ship from needing a massive antimatter fuel gulping reactor and instead a more economical one that feeds the dilithium as it is slowly discharged. Only under heavy loads like full power phasers+shields+hard warp engine use would the system discharge at a rate where the M/AM reactor(s) might not be able to recharge them fast enough.
Anyway, just some ramblings