Subach is very good
Where is the Avenger? Where is the Banshee? Where is the Flail? Where is the S-Breaker? Why did the Alliance replaced all those excellent primaries with a weapon that, while good, is notably inferior?
the Mentu is quite durable for an anti-fighter cruiser (and for a Vasudan cruiser, actually)
Oh! It
is good in the anti-fighter role. But it's still not good enough in the anti-capital role for a cruiser.
If you go purely with statistics, the Fenris actually has more anti-capital firepower than the Leviathan. Its LTerSlash actually outdamages the SGreen over time due to the SGreen's retardedly long reload time. Not that that would save if from anything, being made of paper...
Yes, but the LTerSlash is only useful against something destroyer-sized or above. And we have already seen how badly the Fenris performs against destroyers like the Psamtik.
The Myrmidon is labeled as a Space Superiority because, well, that's probably what it's closest too.
Insufficient. The Myrmidon is a multi-role fighter, something you would build if you were trying to cut the maintenance costs. It should have been labeled as such, unless the Alliance didn't wanted to make it obvious that they were replacing the Ulysses and Apollo with something cheaper and inferior.
It kinds of reminds me to this:
http://en.wikipedia.org/wiki/FMA_SAIA_90Some people had the balls to call that air superiority, even though it was clear, even for a layman like me, that it was only a cheap multi-role fighter with some stealth capabilities, and no match for the real air superiority craft of those years.
Hecates carry more fightercraft than Orions and we all know that an extra wing of fighters in FreeSpace is far more valuable than an extra heavy beam cannon, especially since that said fighter wing can easily disarm the said beam cannon with little trouble. The Hecate also actually has means to defend itself from fighters and bombers, unlike the Orion which has like one blob turret to defend its entire flank which coincidentally has all its heavy weapons. You can approach an Orion from the side and never be targeted by a single point defense weapon, and then disarm all its beams without ever coming under fire.
Granted. That sounds like a good enough explanation to me (altough I still prefer the Orion).
the entire cruiser ship type was to be replaced by the corvette
Yeah, I'll believe it when I see it

. But that sounds like a good enough explanation too.
Poor RNI shipyards though.

I'd be surprised if the NTF had any Hecate destroyers,
Again, it has been canonicaly stated that they had the NTD Corsica.
So:
I mean, there has to be some explanation or some excuse for the Hecate, the Subach, the Mentu, the Bonaerges (this one is practically admitted), the cancelling of the Aeolus production, the lame Fenris upgrade, the Myrmidon as a space superiority fighter when it should clearly have been a multi-role fighter, etc.