In my opinion:
Swarmers-Fine for what they do, useful against fighters and bombers
Dumbfire Rockets- I was surprised by how good they are. Amazing for area denial and steady, no flux explosive damage. 4 of those pods on an onslaught means you can use all your flux for kinetic damage while keeping a stream of high explosive rockets on the target. Devastating.
Sabots- Extremely useful, fast enough to get through most PD and force an overload.
Harpoons- Amazing, but you have to time the attack, it's a strike weapon after all.
LRMs- As per the description, good en mass. No point using them in small numbers, but a dominator or onslaught filled up with them is quite good for fire support.
Salamanders-Probably the most important missile in the game because it's the only way I can catch those pesky hounds, against which it is extremely effective. Very useful on frigates and fast ships
Torpedoes- The buff made them viable as far as I'm concerned. High risk (easy to miss, takes skill to lead a moving target) high reward (4000 explosive damage). 4 of them on an otherwise standard onslaught variant is hilarious. I literally vaporized an enforcer frigate in one salvo of them, the wreck was just gone after the explosion died down. It's also swift death for cap ships,which are very easy to hit. Very good weapon.
Overall they are all good when used properly. PD functions very well, as it should; killing missiles is it's purpose so it better do a good job of it. I think the problem is that energy PD was horrible pre patch, so you could easily launch a few harpoons at it and have them get through. It was fixed though. Now you need to overcome the PD before you launch, which means forcing enemy flux up, overloading, getting an angle to strike a vulnerable point, or just overwhelming the PD all together with LRMS or dumbfire barrages.