1. on a sea map, three boats and five boats shipment plus portuguese let u have 21 fishing boats for free. this lets you conclude the lesser food problem of japan.
2.along with the 21fishing boats method, u construct toshogu shrine for the second age, and then u immediately can get 3 boats from consolute coz u get 200 export for bonus of toshogu shrine after built.
3.the card called fish market makes japan so *** op in a sea map coz u have 21 fish boats and 50 total percent of gathering enhancement.
4.about military, yumi is the second strongest light inf against light inf and cavs. the strongest one should be portuguese skirmishers but if u consider the amount of hitpoints in later age, yumi should be the best coz with full upgrades and those consolute, daimyo enhancement, and golden pavilion makes yumi's physical damage up to 55 and 260 of hitpoints.
5.yabusame archers are the best cavs against artilleries with the strong armor against range damage, the quick shooting rate, 8-9(by shipment) times bonus against artilleries with 18ranges.
6. morutaru is the second bast motor for range but in my opinion the no.1 motor ever with its mobility, 46range(by shipment), and the pop cost, just 3!!!
7.samurai is physically the strongest heavy inf if its totally upgraded and being under the best condition which enhance its power:daimyo, shogun, golden pavilion, and consolute(japanese isolation). because samurai has the high physical damage like 77 in the 5th age with 200 soemthing of siege attack, its also strong against other heavy infs except those mercenaries like hatamoto samurai... although samurai has less bonus for cav and light inf but good armor, hitpoints, and physical damage.
8. but for musks, ashi is the most badass ever. by shipment, 4,5times against cav by melee attack. and 87range attack at maximum with one pop brings u euphoria if u just crush ur ashis against enemy musks. even not so, inf vs inf, how can u usually be beaten with ur ashis? even the opponents have a lot of skirmishers, as long as u succeed in melee combat by ashis, u can own skirmishers. (btw 87range damage means almost same as skirmishers range attack against heavy inf... so hardcore )
9.if u are annoyed by a fort of enemy, u get a shipment from portuguese. the shipment of a battle ship with three petards inside. if u get a shipment, by exp, that makes ur inf's siege attack 33percent more, ur petard's siege attack becomes 2600 to 2700 something like this. ur three petards beat a fort from a behind while ur enemy is attracted by some shots of ur flaming arrows against the fort.
those strong military and dependence on fish boats are the specific points of japan i guess.