As it's been some weeks since I've spent any time playing Starlancer I forget their exact name, but there's a set of missiles that are Fire-and-forget, similar to the IFF Missiles in Wing Commander, which track on anything that's enemy. Barrages of these are quite deadly, and in fact in multiplayer co-op run throughs we've found them to be as lethal to Friendlies as they are to Enemies.
(Reason for this being that the missiles frequently track on the closest enemy, and if there is a friendly chasing that enemy the missiles usually track through said friendly at the same time, which has led my "Team" of players to release bouts of these missiles only under carefully controlled circumstances [such as the launch of a new wing of fighters from a carrier, for example.)
I always tend to balance my loadouts equally between whatever missiles I'm taking (Screamers or the IFF's) and AB fuel. Reason for this is that a number of ships run with Reverse-Thurst (which requires AB fuel to use) and AB fuel is useful for jetting rapidly into (and out of) combat situations.
Typically I also reserve 2 slots of my ship for Jackhammers for two reasons. 1) A kurgen only needs to get hit by one Jackhammer to die quickly. 2) Some missiones require multiplayer Jackhammers for certain objectives. While most missions inform you in the briefing that Jackhammers I needed, I (and frequently my co-op buddies) don't listen to all of the briefing.
Screamers are really most effective at taking out those nasty cloaking Basiliks, Kurgens, and Kamovs. Most of the time whatever else I might fire them at are to slow to get hit.
Though with the large number of capships in the game, I find that most of my screamers go to Turret clearing duties.