I think AM Blaster is (a bit) overpriced too, and too niche. Good for phase ships and maybe Scarab, probably the best weapon for Harbinger now that it cannot use Reapers, but impractical (or at least annoying to use) on nearly anything else. Still, AM Blaster has a niche for hit-and-run ships.
Light Needler at 9 OP, I expect close to Heavy Autocannon (overall) performance. It had a niche when it had 800 range before 0.9a, even if DPS was a bit less. Now, it is an overpriced Railgun or Arbalest as far as I am concerned, which cost 7 or 8 OP. It may have flux efficiency, but it is so expensive for small mounts that it is too hard to leverage that advantage. (Hard to max vents or get flux hullmods and all the needlers I want.)
Another disadvantage of Light Needler bursts is flux spikes making flux management harder. AI does not handle self-inflicted flux spikes very well. And needlers' bursts do not put all of the damage in one shot like blaster shots, but a stream of multiple shots where AI is more likely to lower shield on time, avoid overload, and armor tank the rest of the burst. It is still possible to overload, Onslaught with about five or so heavy needlers can overload ships at times. It would be much easier if the damage was more front-loaded. Shield flicker and self-inflicted flux spikes are why I prefer steady firing kinetics over needle bursts if the latter is not enough to outright overload and paralyze ships like AM blaster salvos can do.
Speaking of overpriced, why is Thumper 9 OP? I might use it bit more if it costs 7 or 8 OP. As it is, I rather get another Mortar or Arbalest (and Railgun is better than Arbalest). Its DPS does not mean much if too much damage is absorbed by armor.
P.S. I even tried Proxy Bombs as a heavy blaster substitute on Harbinger when it had synergy mounts last release. (Because PPT would expire before running out of ammo.) Its damage matches or is close to heavy blaster, and costs no flux, so it should punch holes in stuff, right? Not really. The mines denotated far enough away that it usually punched smaller holes than a blaster, despite the bombs having HE.