Yes, but I meant defensive from the sea, not from land. Are our elves going to build a port surrounded by a chain of islands, perhaps, to limit the number of entry points for ships? Or build a structure like this?
I don't think that's necessary, unless we give Morgoth a navy, something I don't remember any reference to. But if we
don't have them build structures or concern themselves with protecting their sea flank, we could have a battle scene that begins with a group of orcs being smuggled onto the port on small boats at night: a classic sneak-attack move.