Some of this is possible, other parts, not so much:
You can make a missile launcher that fires slow moving missiles, it will not fire another one until the first set are destroyed from, runing out of fuel, hitting target or being shot down. (by virtue of the code) The problem is that the only way you can have 100’s of missile is by having 15 hard points armed with these missile turrets.
Here is my Space Bomb Laucher which does something similar (you might need to lower the speed as i have it set to match my “fast frigates” which is around 0.5)
This one is harder, since there is no mines in the game. The closest we have are missiles. As mentioned earlier, the draw back to the missile code is that the turret can only fire one missile at a time, so your mine launcher can only have one mine on the field at any one time, plus that mine has a designated target which it will try and hit. Nothing will happen unless the designated target comes in contact with it.
Praetorian Industries has mines, i think what they are the most closer thing to a mine. The Plasma mine is the best what i see for now.
About the missile swarm, its possible, but just with fighters and corbettes (if u dl experimentals mod).
If a scuadron has 16 fighters, each one with 2 special Multi Warhead Missiles (4 missiles each launcher) you have, omg, a real missile spam, 128 missiles.
If you use 7 decoys, omfg! 224 missiles?!
Im going to make cruiser weapons addapted to fighters, if you want, i can make them for you tomorrow. Forget the idea about that number of missiles in non-scuadron ships, only a overpowered modded ship filled with missile launchers can do that.
I have two ways to make them:
The Powerful Fighter way:
Weighty but powerfull missile launchers and as result heavy sloooooooooowww fighters. (no more than 0.60-0.75 speed)
Doing this the fighters will destroy anything in the first wave of shots, but after that, they surely are dead. (that depends on the number of fighters and the number of accurate enemy weapons)
The Fighter Suvirval way:
2) Light but powerless launchers and as result Medium/light weight fighters with medium speed (maybe 1.20-1.50 speed)
This fighters will not carry a huge firepower, but they will suvirve more time.
Mines are not possible by now, but u can do a mine kinda weapon using missiles or bullet weapons, just making the speed isane low. If u use missiles, every ship with a scrambler beam or a point defense weapon will destroy every mine u launch at it. This cannot happen with the bullet type weapon (and thats wat i recommend if u want to try this kind of weapon). This weapon should be a very low tracking weapon, very slow and with an insane fire inteval. If u put it on fighters u need to be careful or u will make a super overpowered weapon, only useful against slow cruisers. The tracking speed needs to be very low (about 0.20) so if the mine has a dmg of 200, for example only a few mines launched by the fighters will hit, if u put higher tracking speed, u will destroy a ship when the mines reachs its target. U should be make the range of the mines too high making the mines weapon a tactical weapon, for long range strategies (aka making a group of fighters escort a very slow ship while they launch their mines). The deployed effect of the mine can be easy achieved since the mines are always slower than any ship of the game, when u launch it, the mine will be appear on the backside of the ship (or almost thats the effect it should produce).
I say all of this cuz i already made this “intent” of weapon in one of my mods time ago. The result is not perfect, but of course it can be called “mine”.
About the missiles, u can make a “fake” swarm using more than 2 hardpoints for every weapon, so when u fire, u will see more missiles launched instead of only 1 (but only 1 is the “real”).
I dunno. I never used multiple hardpoints for missiles, i was just saying -.-. Btw, it will not increase too much the number of missiles till u put missiles on all modules. I think xenu wants a spot like the battlestar galactica firing all those missiles xD, but i think thats not possible. Btw, u will need to put all the modules in the same spot to be allowed of firing an alpha strike, and thats very hard. The other option is to make a hull with all the hardpoints in the front of the ship, and make the missiles very fast with low fuel.