Reason I suggest downgrading them is that presently rockets are considered powered and unguided, missiles are guided and powered and travel through the air, torpedoes are powered munitions that travel through water (may or may not be guided).
My problem stems from the description "mark number determines how many missiles are fired in the salvo." In my understanding, rockets are fired in salvos, examples are: rockets pods, MLRS (Multi Launch Rocket System, which can cover a grid square with rockets). Firing missiles in salvo against a single target is often done to counter incoming attacks, which would fall under PD (Point Defense), this includes everything from rockets & missiles to aircraft. I know that multiple missile may be fired against a single target that was too large for a single missile to neutralize. But the system does not model that. Even rocket pods allowed the pilot to determine whether it was a single rocket or the whole pod; and some pods may have allowed more options..
This is really a discussion of semantics, the way missiles are described relate more to rockets to me, and missile & torpedo can be used interchangeably in a space environment, but I tend to see missiles as smaller and carried by starfighters for use against starfighters, while torpedoes are meant to be used against larger vessels.
All in all, considering the other issues in the construction system, this is a very, very, small point.
[EDIT]
Dang, missed that I had sparked more hen one post.
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