I don't understand the soontir/corran fear
They're amazing BECAUSE they absolutely crap on 2 ship builds. Stick them against enough firepower or control (or, god forbid, blockers) and they MELT
They're not pre errata phantoms, not even close (and even against those you didn't need turrets, just a PS 10 stressbit)
It isn't fear though. Nerfing turrets doesn't help the diversity, it'll just make Brobots the next Chirpy/Fel or Dash/Corran.
The mistake is thinking that it is Turrets vs Everything Else, and that nerfing Turrets will make Everything Else equal and therefore more diverse. Instead, add counter elements to Turrets to simultaneously add something to the meta that will situationally nerf turrets.
You don't want to straight up make something worse, because it isn't the PWT itself that makes turrets so good right now. Its all those other things (high PS, movement actions, MOV, etc) that also factor into the issue.
Instead, give the players an option to make themselves stronger against a given archetype.