how about a teck that deals with launchers.
these launchers would only be able to be loaded once every 12-24 hr.... so only can use 4-8 a day. Also you need to produce them on your planet using the facilities...

The planets facility can also be equipped with missile or torpedoes as well they would shoot off if being attacked.

Tier 1 two parts
1st 150k rp Missile production facility missile launcher factory size 1 +1mining 50 attack.
2nd 150k rp Missile launcher.... size 20 limit 4 per ship

Tier 2 300k rp DynniteRokets
attack power 50 cost 10 energy and 50 dynite per to create. 12hr reuse time

Tier 3 500k rp ChrisiumRokets
Attack power 100 cost 20energy and 100 chrisium to create added effect shield degrade 2% 16 hr reload time.

Tier 4 750k rp HydiumRockets
Attack power 200 cost 40 energy and 100 hydium to create added affect 25% chance to drain 10% enemy shields. 20hr relaod time

Tier 5 1Mil rp ErixionRockets
Attack power 350 cost 55 energy and 100 erixion to create. added affect 30% chance to drain 30% enemy shields and restore yours. 24 hr reload time

Tier 6 2 parts
1st 1.5 mil rp Advanced missile production facility
(upgrade to missile launcher facility)Advanced missile launcher factory facility size 2 mining +2 attack 100
2nd 1.5 mil rp (upgraded to missile launcher) Torpedo launcher size 40 4 per ship

Tier 7 2 mil rp PawlaciteTorpedoes attack power 600 cost 60 energy and 100 pawlacite to make. added affect 25% chance to do double damage. 12hr reload time

Tier 8 4 mil rp DieterionTorpedoes attack power 700 cost 70 energy and 100 dieterion to make added affect 35% chance to lower ships defenses by 30% 16 hr reload time.

Tier 9 8 mil rp DysillonTorpedoes Attack power 800 cost 80 energy and 100 Dysillon to make added affect 40% chance to lower enemy attack power by 40%. 20 hr reload time

Tier 10 15 mil rp KureniteTorpedoes Attack power 900 cost 90 energy and 100 kurenite to make added affect. 50% to drain 75% of enemy shields and restor yours. 24 hr reload time.

I'm sorry a one use extra 800 attack power for a billion plus credits with a bit of messing around with shields? Uh... -1.

Love how you use the pics from Supreme Commander 2....Goes Well with the descriptions

err... I think the cost (1B) is for the structure that makes the missile
and then you get free missiles every X hours after that.

not really sure thou.... energy cost makes me wonder....

the dmg is defintely on the low side thou, the highest tier need to at least do 3k to be of much use

1B in one-shot isn't worth it... it should be 1b/missile, if it can repair 75% of your shields...

Ok yeah 1 Billion inital cost could work, but I say do away with the shield shenanigans and just give it a percent boost to attack or something, say 100% on the first hit.