FFG is not going to take unused concept art for ships when there are fully completed and better known versions of those same ships.
I'd actually see the TIE Aggressor having the aux rear arc and the TIE/sf the turret slot. We see the SF turret fire ahead in the movie, while the Aggressor is limited to the rear 200 degrees or so. Personally I left the turret off when I flew the thing in Galaxies, freeing up space for bigger forward guns.
Or you know both imperial ships will have auxillary arcs that cannons can use, or just auxillary ar, and cannons since that seems like more of a what they have doen with Imperials- BobaFett. And no Imperial ship has a Turret upgrade, that i know of. (although the Decimator can use a 360arc...which isnt the same.
If FFG all of a sudden made the imperials start using turrets, then a lot of players are going to need to buy some rebel ships (Kwing for TLT) toget good use of a turret slot ship...an I'm sure it will upset some people.

