I think people have lost sight of a very important issue.
Who wants to be anywhere near a warp core carrying hull with 1500 quantum torpedo warheads when it blows up? They'll have to invent a new word for 'collateral'
And that's before the stardrive section even begins to kerplode.
What makes you think quantum or photon torpedo warheads even have the abilty to "cook off" (prematurely detonate due to external damage).
And if those warheads were vulnerable to cooking off, I doubt it would matter much whether it was 20 torpedos blowing up or 2000. The results would be pretty much the same to the ship in question.
Besides, there are people living in the stardrive section of the Galaxy class which also contains a warp-core/2 torpedo tubes ready to be filled with 250 photon torpedoes and the main deflector dish.
It doesn't really matter one way or the other.
People are expected to be at their posts in times of battle and would evacuate the vessel if the situation becomes dire.