Fan of the Marine terminals here too.
For the cable ends, I was taught to fill 'em up with solder. Strip your wire ends a half inch or so, so the exposed wire fits into the connector just right and the insulation ends up just at the rim of the connector, or even a tad deeper into the connector. You can use a torch to heat up the terminal in a vice and melt some solder into it. Take your already stripped wire and heat it up at the same time. Touch some solder to the wire to ensure good penetration then stick it into the solder bath in the terminal and let it harden.
A this point, you can tape, spray protectant sealant, wipe dielectric grease or vasaline/pretroleum jelly on the terminals. Or leave 'em dry.
If corrosion is a problem, I've heard taping pennies close to your terminals will help keep it minimal.