My rockets do funny damage, what's wrong?
https://cdn.discordapp.com/attachments/447413398695706645/691680763468316742/factorio_2020-03-23_19-10-54.png

Before answering one-by-one, let me post my display first:

When you say it is bug/wrong, what's exactly you feel not working right?

1/ If you mean the two extra sections of "Area of effect size: 11" with "Damage: 10 + 7 Poison", they are not done by my mod. My MRV missiles are simply releasing their respective "smaller" bombs, where my poison bombs are just releasing vanilla poison capsules (see point 2 below). So if some mods changed vanilla poison capsule, everything is changed too. Judging from your extensive recipe menu, guess there are some other mod(s) changing the vanilla poison capsule. You better check that.
2/ If you mean "Cluster size: 6" followed by "Cluster size: 2", it is because I am distributing 8 poison bombs by one poison MRV missile, and each poison bomb release 6 poison cloud. Poison cloud has relatively much smaller radius than things like atomic wave. I have to allocate 6 bombs to outer ring and 2 bombs to inner ring, in order to cover the target area. Factorio game is not that intelligent enough to aggregate them into the same display entry.
3/ If you mean it is expensive (huge money), then don't use it. If you count carefully, there are 48 poison clouds generated (and I tried to reduce overlapping area), and the ingredients are approximately that of 48 poison clouds (or 8 poison bombs) as well. (Of course, if other mods modified the recipes, it is not my problem.)

Sorry, I thought if the Schall Endgame Evolution is worth it, then these missiles will be able to oppose something to the aliens. But I did not expect that I would receive damage as in a vanilla game.
Could you add a modifier to adjust the damage? Or untie the damage from vanilla missiles?

I am not sure if I read your comment correctly.

But I did not expect that I would receive damage as in a vanilla game.

What did you expect then? Do some mods allow you to immune from those AoE damage?
Which setting is wrong in vanilla game, to give you such expectation?
(The only type that players can have legit immunity with, is poison immunity when driving any vehicles and tanks.)

Could you add a modifier to adjust the damage? Or untie the damage from vanilla missiles?

For 0.16 and before, yes. At the old time, there are two separate tech (damage and shooting speed) for EACH type of bullet. I would have done the same, like all other bullet type.
But since 0.17.0 all those tech were merged. Grenade, land mine and rockets were merged together. Missiles are like enlarged version of rockets. I do not see any reasons why missiles need to have a standalone tech.

But adjusting the modifier is possible. Are you wanting to nerf or buff missiles (compared to rockets)? And what is your reasoning for that?

Some mods allow you to configure the basic damage of weapons through settings without technology.

For example, Orbital Ion Cannon adds a weapon that deals 2500 damage. Against aliens from Schall Endgame Evolution, these are ridiculous numbers, and the cost of technology is huge. But the author of the mod made it possible to adjust the damage of his gun. Thus, I changed the base damage from 2500 to 250,000.
https://cdn.discordapp.com/attachments/447413398695706645/692315309226459166/OICD.PNG

I didn’t suggest buff or nerf your missiles, but only suggested adding a basic damage modifier so that I could adjust the damage to my mod assembly. If possible.

I am a bit reserved on providing it as an mod option.

Orbital Ion Cannon is a different thing. It is a sci-fi weapon that has little resemblance to other weapons. Balance is not an issue. And it is some kind of superweapon, so players (including you) buffing damage a lot does not cause balancing problem.

On the other hand, my missiles are merely just "packed" and long-range version of rockets. So they are not comparable to the sci-fi weapons, which can be set freely.

My MRV missiles are simply reusing the projectiles of the base rockets, so the base damage values must be the same as vanilla (and my Schall Tank Platoon mod) rockets. So are you asking for the base damage or damage modifier? They are two different thing. (The option of Orbital Ion Cannon is about the former.)

About the former, I am not sure if it is possible to just change the missile damage without changing its base rocket damage. Maybe it has to go back to adjust vanilla atomic bomb, vanilla poison capsule, Schall Tank Platoon napalm bomb or vanilla "fire-flame". (BTW, this means the balancing lies on vanilla game or your mod set, not on my part.)

In principle, I do not like offering options to allow players to change the later (damage modifier), and relying on players' self-discipline.
It means the author has given up balancing effort, and players will likely abuse the option to make it OP, then later find the game monotonic.
On mod programming side, if modifiers in technologies are involved, technology effects recalculation has to be enforced every time to keep values in consistency. It is a bad thing and I do not like this at all.