I am on the one hand totally in favor of supply limits in modern navy & “space navy” simulations. Pound for pound, missiles are more effective than direct fire weapons. Playing Full Thrust or even SFB with factions that favor missile-heavy fleets can be an exercise in futility: turn 1, player A makes a move. Then player B plonks down 1,000 missiles. Use your imagination about what happens next. I’m FOR ammo limits because in any ONE battle, missiles SHOULD rule the battlefield. But they should impose a HUGE logistics cost on that fleet. Meaning that same fleet, in battle two, should have to worry a LOT about whether those missile magazines are full or empty or half-full. David Weber does an OK job of representing this concern in several of his Honor Harrington novels.
On the other hand, in GSB, I am against this kind of retroactive supply limit. As Cliffski noted, the entire game has been balanced predicated on some kind of “lets make missiles out of vacuum” projectile paradigm. True also for Tribe kinetic weapons, btw. If we were to make this kind of switch, the entire game would need to be rebalanced. Missile spam fleets, already a pain in the tuckus to deal with, become potentially overwhelming…or potentially foxable (“Here’s me with my Missile Attractor cruiser, sucking your ammo to zero and there’s nothing you can do about it because the AI isn’t smart enough to figure that out and not fire at it”). The Swarm’s missile futzer thing becomes that much more powerful. As-is, it is delightfully balanced in the GSB universe–missiles can still get through, but one can’t easily use missiles as a futzer-equipped Swarm player, and it all seems to work out in the end.
As Cliffski suggests, an entirely new weapon that has countable ammo is a possibility–and it shouldn’t be too hard to fit such a thing into our current mix of weapons and defenses.
But my first point is, I think, most salient. Ammo is a strategic consideration, while GSB simulates tactical engagements. I could see some kind of supply requirement in sequential battles in campaign mode–if one builds bases, then maybe X number of bases are required to fully arm Y number of missile launchers, and falling short of the needed bases imposes a supply limitation–but for any one GSB battle, I think we’re better off with infinite missiles, as essentially silly as that may appear.