The 9K needs the gauss, it's the only viable weapon since you can't fit dual ac5/uac5 or an ac20. Leaving the ballistic hardpoint empty isn't a really good option.
Couldn't it get 10+5% instead of 5+5% on gauss and ballistic cooldown? It's reasonable, it won't make it into a beast and it'll still be way down the pecking order.