One question I have is that it takes an action to rotate your arc, so that means
1. If you are stressed, your ARC is locked
2. It seems like you will always be hurting for actions / poor action economy.
I want to like this ship, I like the look of it aesthetically, but I wonder why you would take it over a ship with a PWT. If someone would enlighten me, I'd appreciate it
The Shadowcaster specific mod allows you to rotate it without spending using an action as long as you moved speed 3 or faster.
As for why you'd want it over a PWT, it's still a firing arc. Any abilities that require arc will trigger and autothrusters won't trigger (other than at range three).
Think of it as a much better Firespray with a rear arc that can be moved. No one craps on the Firespray because it's 'too hard' to point the rear arc somewhere.