also, the "middle ground" for hullmod op cost this system is intended to balance around is 25 OP (at capital size), right? EMR is 30 OP. Why is a 33% debuff to such an important stat as rof for a hullmod that is 5 OP over the middle ground even remotely acceptable? like, other people have said, "building in a 25 op hullmod instead of EMR is equivalent to a 15 OP hullmod that boosts missile rof by 50%" which "might be more interesting" but 1. i disagree that that wouldn't be a no brainer in most circumstances but more importanly 2. is wrong bc it would be the equivalent of a 5 op hullmod
overall a debuff this severe to a stat this important feels just completely out of whack
I'm going to be completely honest here, for some reason in my head the OP cost for the capial tier was 40. ... oops? I think it got mixed up with heavy armor or something, in the "build this in always" tier. So, I'm really glad you brought this up. Let me change it to 20%, at least for the moment; open to suggestions!
For 5 OP, though, 20% feels like it should be alright - perhaps a bit much on the face of it, in pure dps terms. But that's only a concern for some missiles, and in that case giving up 5 OP to build in something else could be fine. And for the more ammo-limited missiles, it wouldn't be that big a deal (nor would it on ships with FMR). So it seems like there are a lot of considerations here which might push it one way or another.
My bad, I also got it wrong. A 20% drop in rate of fire means that the equivalent 5 OP hullmod gives +25% rate of fire. That does again seem like a no brainer on missile boats since 5 OP is very little, worth 1 PD laser. Can't think of a situation where I would not install that hullmod on a missile ship and just skip 1 PD unless specifically trying to make it fire slower.
Here is a table - 1st row is EMR penalty to rate of fire, 2nd row the bonus from the equivalent 5OP hullmod (ie. modding in a neutral S-mod instead and paying OP for EMR is equivalent to installing this 5OP hullmod)
EMR malus% -50 -47.5 -45.0 -42.5 -40.0 -37.5 -35.0 -32.5 -30.0 -27.5 -25.0 -22.5 -20 -17.5 -15.0 -12.5 -10.0
5OP mod bonus% 100 90.5 81.8 73.9 66.7 60.0 53.8 48.1 42.9 37.9 33.3 29.0 25 21.2 17.6 14.3 11.1
EMR malus% -7.5 -5.0 -2.5
5OP mod bonus% 8.1 5.3 2.6
This one gets trickier to balance. 5OP is so little that even if it just gives +10% ROF it is a strong hullmod for a missile ship. On the other hand if it gives like +2.5% ROF then that makes it very spreadsheet-y and probably gives the player a weird feeling.
And remember that 5OP is for capitals so it's really insignificant OP for the effect. For a destroyer the missile rof boosting hullmod costs 2OP. Basically this risks making S-modding in EMR a newbie trap and a somewhat insidious one, since it's not immediately clear how bad of a trade you're making unless you math it out.
One fix would be what several people have suggested - apply the nerf to EMR whether it is S-modded in or not. Else it's likely going to be always install on missile ships but never S-mod in.
Some alternatives: make the base hull mod actually cost 40OP for capitals so S-modding it in with a slight malus is worth considering sometimes. Or give it the SO treatment that it can't be S-modded in at all, kind of reasonable since it is a hullmod that is basically always a great choice or never never a good choice depending on ship so the choice of S-modding it is not very interesting unless one of the other alternatives is applied. Well, it might be interesting still if the others give bonuses worth considering.
(R code to generate table)
m <- matrix(data=seq(-50,-2.5,2.5),nrow=2,ncol=20,byrow=TRUE)
for (i in 1:length(m[1,])) m[2,i] <- 100*100/(100+m[1,i])-100
round(m,1)