To be honest, I as a PA player use them for target practice.
But in all seriousness it's speed is what makes the Sacheen a dangerous weapon if used correctly. I use it for hit and run tactics and the Defender squadron it spawns can be integrated into this incredibly well. Best used paired with CR90 Corellian Corvettes so while the Sacheen attacks the frigates, the CR90 wipes out the fighter screen, and when it seems you made your mark just use the power to engines and run for it.
Wait for the shields to recharge and repeat.
Hope this will help you out a little bit.
Oh, and before I foget, I don't think the Engine was intentional. I think it is just a glich/bug that the engine hardpoint is practically linekd to the Hull.