I looked around and saw some of my thoughts already listed, so I'll avoid writing those out. If I error and repeat, please forgive. TL;DR is at the top for convenience.
<TLDR>
1. Swords, guns and rifles
2. Swords, guns and rifles that kill your enemy
3. Boarding a ship, killing the crew, breaking their guns, taking the helm and crashing it into the dirt
4. New class, the Marine, used to board ships
5. Co-op Campaign
6. Factions and Nationalities
7. New Ship type: Single Seater Biplane, Two Seater Biplane
8. New Map, with some wildlife
</TLDR>
1. I saw someone suggested swords. Yes to swords. And pistols. And flintlock rifles.
2. I don't see why those can't be used to fight with as well. Obviously, they're going to be very underwhelming against a whole ship, but the feeling you have, being able to use a personal item, would be worth it. I'd find myself using it just before an enemy ship goes down, or just before mine does.
3. No, they won't do it. But I'm required to mention it.
Ship to ship boarding. C'mon, my name is Marine Ninja. Hand to hand combat is in my blood. This would really open up some interesting dynamics. This unhinges the dynamic of no one dying until their ship dies. To help keep some of that balance, we continue to keep players safe from ship mounted weaponry, and vulnerable only to very very short ranged pistols, rifles and bladed weapons OR implement the following: players do not die from ship mounted weapons while mounted on a post (weapon, helm), turn on friendly fire to prevent those who are boarding from being invincible and introduce a 4th class; the Marine, who specializes in ship boarding and hand to hand combat. Class items include all weapons mentioned before, as well as dynamite to sabotage, grappling hooks to ensure safe ship boarding (toss a line across to pull yourself aboard the ship, toss back to escape to yours), a torch to try and set things ablaze and perhaps "martial skill" to improve character stats, or to enable combat moves like a chokehold.
4. I know, I'm sorry. But my ancestors demand it.
4th Class; The Marine. If ship to ship boarding isn't fully implemented, we could still have one character type who is allowed to jump from ship to ship/shimmy along harpoon lines to subdue the enemy crew with chokeholds and stab wounds to temporarily disable them (I'd also like to throw characters overboard, please), dynamite to throw a party (sabotage party) and torches to start a cookout (of epic proportion).
5. Campaign Mode: The single player, when it first came out, was hard. If it weren't single player, but a multiplayer survival/campaign mode, I'd be back at that in a heartbeat. This is the biggest reason why I love borderlands and mario wii (don't you judge me).
6. Nationalities and Factions. Captains should be able to pick a faction that they and their crew are part of, giving a bit of flavor to the ships. Players like Marine Ninja, who desire to have the moon itself, would enjoy the flavor of selecting various nationalities for character models. I like my character talking in Japanese, with the subtitles at the bottom, like all my movies. Can I have some French, Russian or Spanish now too?
7. I want to fly a single seater biplane (and then later a two seater) and strafe enemy boats all day long. ALL. DAY. LONG. Captains who select the single seater would command 4 planes (three pilots plus self in single seater planes) and 2 planes if the two seater was selected. Pilots can be daredevils and step out of the pilot/gunner seat and stand atop the wings, which would be required for some repairs. The Captain is able to select the weapon loadouts for his 2 or 4 craft, meaning there's still plenty of strategy available.
8. Look, I'm getting greedy and I know I said I wouldn't list things I had already seen listed... But can we have a new map brainstorming session? To start it off, I'd like to suggest that this map have some form of wildlife. Masses of geese that scatter/die when shot with flak, wind whales, armored dragons or some sort of sky dolphin...
Hey, thanks for reading.
(jk,l) MN (op)