This does come back to offering players false choices. When the ion cannons cost mountains and aren't worth a hill of beans it feels like a rip off and people have to be wondering what is wrong. I'm really hoping you guys do focus on making everything useful and have their usefulness reflect the cost. At it stands now, the ion cannon should be worth maybe the cost of 1 starship.
Actually the "buying an ion cannon from a trader is a ludicrously poor investment" thing is quite intentional. That's just candy to trick you into thinking you can trespass on the AI's privilege of having them 
But capturing an ion cannon from the AI should be worth at least something.
Why can we build ion blasters then?
I like this idea alot. But I think that it should double in power per tier, rather than linearly increase, to better match that of fleet ships.
This because ship stats seem to approximately double on each tier up, so Ion cannons ought to follow that scale.
Actually the fleet ships increase linearly too, as in the code literally multiplies the mkI's health and damage (and a few other stats, but NOT rate-of-fire or anything that would lead to a quadratic/exponential increase) by the mark level. So mkII is twice as strong as mkI, and mkIII is three times as strong as mkI, but mkIII is only 1.5 times as strong as mkII.
But to some extent the really high mark ion cannons could stand an extra buff since they can already insta-kill most of the targets they actually face.
Well, I was partly incorrect, but considering I just checked the stats of the mark I to markIV fighters, I noticed something interesting.
The costs of each tier of figher is twice the previous tier, while the stats are always a linear increase. Depending on your definition of combat value (I am using Durability * Attack power), This may or may not make sense. Mark I fighter costs 2x as much as mark I, while Mark II have 2x as much damage and 2x as much health, hence 4x the combat value. Mark 3 have 3x the stats of Mark 1, hence 9x the combat value, or 1.5x that of mark 2, and 2.25x as much combat value. Mark 4 have 4x the stats, 16x, 4x, 1.8x, the combat value, hence from each higher tier, the improvement is lower. I am not sure if this is intentional or not. the lower tiers become much more powerful for their cost, while the higher tiers become stronger much slower for their cost. T5 continues the trend as well, with 1.5x as combat value, but once again the same 2x cost as mark 4.
(Note I am assuming all ships scale the same way, I am not sure if this is the case)
Mark I 1x(1x) stats, 1x cost.
Mark II 2x(4x) stats, 2x cost.
Mark III 3x(9x) stats, 4x cost.
Mark IV 4x(16x) stats, 8x cost.
Mark V 5x(25x) stats, 16x cost.
However, Since we are balancing an attack, I would note that only the durability stat really matters here, so it is a linear increase, rather than a quadratic one.
Also, potentially multishots if attacking significantly inferior ships would be interesting as well, so a MarkV attacking a fleet of MarkI ships would get a 16 multishot (would obviously require the spread shot mechanic to work properly)
Having the number of shots be dependent on the mark level of the target is a no-go, sorry. The number of shots per salvo needs to be static. But in this case I wouldn't want it to increase for the lower marks anyway: "ion flooding" is and should be a valid tactic. There are other ways of handling swarms of lower-mark stuff. But having a higher rate of fire in general would be a good thing.
An ion cannon currently fires at 1 shot per 2/4/8 seconds (depending on ship cap I think) and for the basic fleet ships, the fleet cap is 49/98/196, so it currently takes 392 seconds (~6.5 minutes) for an ion cannon to take out ONE fleet cap of ONE tier of ships.
Yea, that's not fast enough, I agree. And it's very very poor against anything higher mark than it. Of course, making it so that ion cannons can do non-zero and non-infinite damage to higher-mark targets based on mark is going to involve more code than I originally thought, but I think it's worthwhile.
I think that increasing the fire rate to 0.5/1/2 would be better, except that may attack speeds were increased so as to be at least 1, so keep the same cooldown, but get 4x the fire rate. this would allow for a matching tier fleet cap to the ion cannot to be taken out totally in ~1.7 minutes.
Minimum seconds-per-salvo time is 1 (used to be able to do it on partial seconds but we removed that to get some significant optimization), and personally I don't want it to fire any more often than 2 seconds (on high caps). And on lower ship caps the time needs to be 2x and 4x that due to the nature of changing the cap scale. But multiple shots per salvo is quite doable.
Sorry, I meant 4x shots, not 4x fire rate. And I knew you had a reason for upping the minimum fire rate as well. On lower ship caps any ships that do not scale need to have their attack speed/attack targets scale with the ship counts.
Of course, the first player to run into an AI Eye under a forcefield next to a superfort with 2+ ion cannons is probably going to kill me for this
They will probably kill you anyway, for setting up the RNG XD
