Reduce they're max effective range to railguns to 8000-10000.
Theyre to OP at 15000 and are to hard to chase down. Let them have their 1 shot Slug gun and when they miss we'll have a chance to close the distance and have a chance against them.
I always thought the gunships was going to be like a Warcraft pvp Fire mage, class cannon, a big BOOM but If you get in range theyre dead.