Preface: I don't use SO, this is all for non-SO ships (except the bit about machine guns, because they really have no other use).
I would say Light Mortar is a decent weapon for what it does, it's just that anti-armour guns in small slots suck, unless they hit like a truck (Anti-matter Blaster). I would say LAG is worse than LM, because LM has a better hit strength and is way cheaper.
I also agree with intrinsic parity in that while needlers are good against shields, they do nothing else.
Your low rating for dual flak cannon, and suggestion that HMG is a better point defence weapon, makes me think you did not use dual flak cannon at all. It is more expensive than single flak cannon, yes, but it's worth it. It's ability to stop missiles in their tracks is unparalleled, be they single or a massed wave. AoE attack is just that useful. It's second best PD in the game, after Paladin PD, though unlike it, it can be mounted on mounts you actually can spare for PD.
In addition to that, Heavy Machine Gun is a knife fighting gun, just like all other machine guns. It being PD is a nerf if anything, because it means it gets distracted with shields, instead of wrecking the shields of the schmuck in front of you.
Mjolnir would make most other weapons obsolete... If most ships could afford to fire it. Most cannot.
You don't use Heavy Mauler, Heavy Mortar or Gauss Cannon? Huh.
You are rating Pulse Laser too high. It's sustainable, but it's not actually very versatile; while it deals energy damage, it's still mainly a shield breaker and it's good efficiency might not mean much, if it's DPS is too low to allow you to exploit opportunities. Ion Pulser is everything Pulse Laser wants to be.
Mining Blaster is trash, I agree, but Heavy Blaster? It's tied for the best medium energy weapon with Ion Pulser. It seems inefficient, but the trick is, most high-tech ships can actually support it, if they have to, both flux-wise and with mobility. And if they can, you basically have a large weapon in a medium slot. While on some ships you don't need them (Medusa and Shrike can get ballistics and phase lances for better efficiency against shields. Wolf, Doom and Paragon are better off with Ion Pulsers instead), on others they are your lifeblood and while you can not use them, you still should. Ideally paired with an Ion Pulser, it's such a great combo.
You are also too harsh on High Intensity Laser. In vanilla, it's hard to find a ship where you can pair it with some ballistics (Prometheus Mk II (l o l) and Champion), but, for example, HIL Sunders melt armour and hull, whether just by pressuring an enemy into not letting your shields down ever, or if they can fire at someone with impunity. It might not deal hard flux, but it's the best anti-armour gun in the game, besides missiles and anti-matter blasters, who both have limited ammo and cooldowns.
Hammer Barrage is actually better in one metric than Cyclone: DPS. The one ship that can really make use of it is the Radiant, and oh boy, does it go to town with them! If you intend to fight more than a single ordo at a time, though, you are better off with Cyclone, since Radiant seems to have stuck the trigger for Hammers open and it runs out of them too soon...