I had a Correo with the very same loadout (Luberos are class8 Hullbustern no?), and I had a hard time killing the more advanced transports. The biggest thing I managed to kill in it was an unarmored P-Trans.
Since the Class8 Guns don't do enough hull damage (even over time) it is a good Idea to kill the targets shields and nuke mine the hull. You could try a 4 shieldbuster loadout for this too.
I finally sold the Correo because its simply to weak compared to the other 'combat' freighters. The Grizzly, Bactrian, Anki and the CSF have simply more firepower.
Imho this beautiful ship either needs class9 guns/class5 turrets or a fighter torpedo slot:)
Just go for all salamanca/angelito turrets/guns, with 2 tizonas on the class 9 slots. It will give you the power to obliterate sheilds and do a considerable ammount of hull dammage.
4 shield busters will compromise your ability to dammage large ships' (transports mainly) hulls too much, while 2 tizonas will still make short work of any sheild.
Something like;
2 x Tizona del Cid
2 x Salamanca Mk I
4 x Angilito Mk II turrets
will do you perfectly well
Im thinking of this in terms of pure gun use, i.e no mines/missiles or such like, which is how i'd use it. Im sure if you are good with a mine, a nuke will do admirably.
As for the CSF comparing to it, the Correo is much more durable. The CSF is also kept in balance by a Class 8 gun slot that's pretty much just Debilitator fodder.
My loadout for the CSF is Two Class 9 Deb IIs, a Class 8 Deb II, and all Barrager turrets. Not really much wiggle room for anything else. Four turrets fire forward, two only face backward. So that's four hullbusters and presumably a nuke mine.
Im fixing my rep right now to get one of these and i too will be using it for some RP smuggling but not pirating as ill have a smuggler ID and a Corsair tag. I think it will be fun to do some smuggling for the Corsairs and reading the weps suggestions are very helpfull. Thanks.
If you want to meet up and do some smuggling runs some time Dancing Lady then my char name is A.Ferrara.