Light Ships have small hulls, and this means they're incredibly vulnerable when they get made the target of an enemy ship. They're best off hiding amidst a large fleet from small enemy fleets. For example, if you're in multiplayer as Japan and have just westernized when the HRE declares war on you, they might field a fleet with 20 galleons and 60 cogs to your neck of the woods. In this scenario, if we say you're fielding 120 ships, and the best you can get is caravels and barques, barques in this case will be much more valuable, as they will inflate your positioning whilst risking much less damage, so you might take say, 1/2 big ships, 1/2 light ships. The enemy's ships each pick their target at random, and meaning half of those 20 galleons will pick one of your caravels. So even if you lose all the barques that get targeted, that's only 10, and, assuming that none of the 10 galleons that did it hit hull/morale 0, 5 of those would expect to move on to caravels. Meanwhile, your fleet (assuming remotely similar admirals) will have a much higher positioning value, to the point that your caravels would actually be doing enough damage in the fire phase to sink some galleons in 1 or 2 phases.
This is a fairly rare situation, of course, but the point is that so long as you aren't pushing 5-6000 guns, a fleet that outnumbers its enemies will benefit from extra light ships by effectively buffing the big ships through positioning bonuses, at a fraction of the cost of more big ships.
This is a fairly rare situation, of course, but the point is that so long as you aren't pushing 5-6000 guns, a fleet that outnumbers its enemies will benefit from extra light ships by effectively buffing the big ships through positioning bonuses, at a fraction of the cost of more big ships.
