There are two ships in "Tales of a Sea Hawk" which don't belong there. In Silehard's squadron to retake Bridgetown, the Monarch is an Essex class frigate, which is defined in "Ships_init.c" as only appearing in the "Napoleonic" period. In contrast to a ship from the future, Brian the Slayer, one of Silehard's pirate friends in the battle at Cozumel, has a Fast War Galleon, which according to "Ships_init.c" shouldn't exist later than "Golden Age".
I've vague memory that in older versions of the game, Monarch was another battleship, though I also remember a corvette being there - the Bridgetown squadron used to contain four ships, not three. The character definition file "Story.c" includes Lewellyn Belt, also with an Essex class, though he currently does not appear in "quests_reaction.c". I suggest putting the Monarch back to being a battleship and re-instating Lewellyn Belt with a lesser frigate, possibly an "Aurora" class. (If one of the ships was removed because three battleships plus a frigate was too difficult, maybe only assign the Monarch if you're playing one of the higher two difficulty levels.)
As for Brian the Slayer, the plain wooden finish Constitution look-alike, "SuperFrigate", alias Iceni Queen, is available in "Colonial Powers". (In fact, it's even available in "Golden Age"!) Perhaps he could have one of those. Otherwise maybe give him a "Crimson Blood", which is a pirate retexture of an "Aurora", different to the "PiratCorvette" which you may already have met if you took the "Sink the Pirate Corvette" side quest.
I've vague memory that in older versions of the game, Monarch was another battleship, though I also remember a corvette being there - the Bridgetown squadron used to contain four ships, not three. The character definition file "Story.c" includes Lewellyn Belt, also with an Essex class, though he currently does not appear in "quests_reaction.c". I suggest putting the Monarch back to being a battleship and re-instating Lewellyn Belt with a lesser frigate, possibly an "Aurora" class. (If one of the ships was removed because three battleships plus a frigate was too difficult, maybe only assign the Monarch if you're playing one of the higher two difficulty levels.)
As for Brian the Slayer, the plain wooden finish Constitution look-alike, "SuperFrigate", alias Iceni Queen, is available in "Colonial Powers". (In fact, it's even available in "Golden Age"!) Perhaps he could have one of those. Otherwise maybe give him a "Crimson Blood", which is a pirate retexture of an "Aurora", different to the "PiratCorvette" which you may already have met if you took the "Sink the Pirate Corvette" side quest.