I guess, I have to make this easy (for myself). And start from scratch. Henceforth the deletion of the entire first post.
For my game:
I have these fast moving and slow moving projectiles.
Attackers might fire from close by or far away.
Targets might move around too, during the battle. Only then, this mechanic comes in action.
Attackers too, can move around while they fire. But this of course brings extra problems for the attacker. But it might be a strategic choice like a retreat or such.
But here is the thing. I kinda have trouble getting the mechanics around this "want it all", right. It is constantly half-assed crap that doesn't cope with reality somewhere.
That the mechanics don't work was an accidental discovery. This due to the fact that I wanted slow moving projectiles as well (cheap artillery and stuff)
There are only 3 statistics to work with, divided into 4:
R -Range of the attacker.
St -Speed of the target.
Sa -Speed of the attacker.
H+/H- -Adjustments to the speed of the projectile (faster or slower, H stands for Homing).
From this, I like to derive a penalty number. This number is going to be 0=good, to 6 or higher=a complete miss. The numbers in between are going to be an extra accuracy roll.
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How would you deal with this? How would you determine the penalty number?
Changed the above post into a different approach. I hope I can get an solution. Because having a natural RPS effect on structures is an absolute wish of mine.