The De Leon would be very good in low point games I think. That’s a lot of cargo and decent speed, plus a couple very good cannons. I’m not sure how I feel about her yet.
The way El Catedral is worded, it should be more than 5 gold. Unless you want to make it like the other forts that have a similar ability, and cap it at just +1 if there is gold unloaded there. It wouldn’t take much to give it +3 to cannon rolls, making them almost automatic.