Ok, here's my thinking: Maresian Sea-Guard would have fewer combat-capable vehicles, owing to a greater need for transport ships. As a result, they are extremely frugal with parts, doing their utmost to salvage every single engine, gun, armor plate, etc. This also fits in with the "pirate salvagers" theme.
Owing to their homeworld, the Maresian Sea-Guard would make use of trained and cybernetically enhanced dolphin-like creatures as underwater scouts. These creatures are used sparingly, as the cybernetics and training to make them are costly.