Any Core Rules updates that Mongoose is planning for MgT definitely needs to address the missile-damage issue. They are far to weak as they currently stand.
Based on
CT Book 2 (from which MgT apparently derived its space-weapon concepts) I suggested up-thread that missiles could do 1d6 x d6 damage. McPerth pointed out that multi-warhead missiles in MgT-HG already do that, so they (and other warhead types and torpedoes) would need to be rescaled as well in order to fit the new paradigm.
Suggestion:
Standard Missile: 3d6
Nuclear Missile: 6d6 + Crew Hit
Multi-warhead (Submunition) Missile: 1d6 x d6
Torpedo: 5d6
Nuclear Torpedo: 8d6 + Crew Hit
Bomb-Pumped Laser Torpedo: 6d6
If necessary for scaling, one could adjust the damage of certain warheads downward to base 1d3's instead of 1d6's.
In any case, at least for HG, the main issue with missiles is that they are too vulnerable to PD (sandcasters and lasers) fire. By raising the dice, they will somewhat overcome the armor, that's true, but they will still be so.
See that (I asume TL 10 due to this being the numbers already made) if you asume nukes to be 6d6 damage, a salvo (let's say 100 missiles, to make numbers easy) would be 600 - missile - 6. Assuming gunners 2 and FC software +2 (maximum at TL 10) against a 10 armor ship with some sandcsters and lasers, barrage damage would be 2d6 + 2 (gunners) + 2 (fire control) against a defendive modifier of 1d6-2 (sandcasters) + 1d6 -1 (PS lasers) + 10 (armor) - 6 (dice/weapons), so it would be 2d6 + 4 against 2d6 + 1 (+3 if dodging). Radiation damage would be ignored, as the ship has armor 10 (so over 8). On the same roll in both sides (and assuming Dodge) result would be 1, so no damage. Quite more than as written now, that's true...
PA turrets in the same conditions would have the same offensive modifiers, but de defensive modifiers would be just armor minus weapons (so 2d6 + 5 - 7), and if the PAs have high yeld they have and additional +1 and very high yeld (after all they are TL 10) +2, so the barrage roll would be 2d6 (no modifiers). If the target is dodging, again 2D6-2, so will scaore damage on a 5+ (albeit less so than the missiles).
Here we must know if the missiles can also be high yeld, or, in any case, they can ge accurate, so giving them an extra +1...
At TL 15, things favor the defender, as the FC has a máximum of +5 (so 3 more than in the example), while armor may be increased up to 15 (so 5 over).
Same way, if gunners are assumed +3, then the offensive modifier would be +1, but so will both PD rolls, with a net -1 to the missiles (PAs would receive only the +1 offensive modifier).