These are generalizations about each ship line. Keep in mind there are exceptions in every line but that's not the point of this post.
Japanese Destroyers: Stealthy ships that rely on remaining hidden and using torpedoes to destroy ships. They're vulnerable to gunfire from nearly every ship and their guns are pretty bad. These ships sneak around and try to delete battleships. Not very easy to do these days as you get to higher tiers because of various nerfs to torpedoes. These ships are feast or famine - either you do really well or you do almost nothing in them. Their smokes are meh - blow for a bit, last a little while, best used for escape. Best ships: Shimakaze, Kagero, Akatsuki, Kamikaze R.
Japanese Destroyers Sub Line: This is the 'gunboat' line of the IJN Destroyers that only contains one gunboat - the Akizuki at T8, which boasts 8 100 mm guns but only one torpedo launcher with four tubes. This line is characterized by having access to the torpedo reload consumable, that, when used allows them to fire all their torpedo launchers after five seconds. This lets Akizuki fire a modest 8 torpedoes about every 4 minutes. This, however, brings us to the best mid tier IJN DD - Shiryatsuyu - a 'gunboat' that can fire 16 torpedoes at once because of this consumable. I don't recommend this line to new players as the dramatic differences between Shiryatsuyu and Akizuki require drastically different captains, which can be in short supply when you start this game.
Japanese Cruisers: These are some of the more forgiving cruisers in the game. They are given large cannons for cruisers starting at T5 with the Furutaka. They're fast, stealthy, and good at staying at the back and lighting enemy ships on fire. They're also nimble and have decent armor to bounce cruiser shells if you angle. Best in the line are generally the Furtaka, Myoko, Atago (this is a premium) and Zao.
Japanese Battleships: These battleships are fairly thin armored in the beginning and get more armored over time. They have very long range guns and are very accurate for a battleship. They're sublime at deleting cruisers and other battleships at the lower tiers, starting with Kongo. However, getting to Kongo is a real pain as the Kawachi and Myogi are awful. Best ships are Kongo, Fuso, Nagato, Amagi, and Yamato. Getting to the Yamato is worth it.
Japanese Carriers: As of May 2017, these are basically the only relevant carriers in the game. They get to have at least one fighter squadron while also having multiple strike aircraft squadron. This makes them considerably superior to USN carriers with one exception - to be seen below. Best ships? Lol all of them though I'm sure I'll be corrected to that.
USA Destroyers: Crazy fun ships most famous for their rapid fire guns, starting at the Nicholas B hull where you get guns that fire every 3.3 seconds or less. The USN destroyer line has pretty bad torpedoes that are only good for ambush up until Tier 7/8 so they rely on entering capture points and killing enemy destroyers. They have a crazy long smoke duration allowing them to pick a spot, smoke up, and spam high explosive at enemy ships until they are burning nicely. They're also famous for the ability to easily fire over mountains. Finally, to reinforce their role as support/AA picket ships, these destroyers have the option of swapping speed boost for defensive fire fairly early on. Notable ships include Clemson, Mahan, Sims (this is a premium), Benson, Fletcher, and Gearing.
USA Battleships: Heavily-to-decently armored bow tanking ships that start off slow and eventually become faster and more modern. Known for their ability to shred air planes. They're great at medium to short ranges. Favorites usually are New Mexico, North Carolina, and Alabama. Missouri and Montana are popular among some these days the first because of it's insane ability to print credits and the latter because of its heavy broadside.
USA Cruisers: A mixed bag, that changes a lot through the line. It only really gets good at the New Orleans (T8) on up where their armor piercing shells become ludicrously powerful, and their own armor finally gets thick (relatively). Cleveland at T6 is an exception as it's a great fire starter and plane shredder due to it's crazy AA DPS and Defensive Fire. Des Moines is the holy grail because it has a really short reload (5.5 seconds) despite it's large guns. Their radar, starting at T8, is medium range (~9-10 km) but long duration (over 30 seconds) These ships are characterized by their stupendous ability as support ships, through use Defensive Fire, Radar, and once again, glorious 8" AP.
USA Carriers: As of May 2017, the only good USA carrier relative to Japanese Carriers is the Saipan, which is a premium. This line is characterized by its ability to either go full air strike (lots of dive bomber squadrons with only torpedo bomber squadron, no fighters) or air superiority (lots of fighter squadrons). The former means you can't protect your other team mates from enemy planes, the latter means you can't do much damage in the fight besides shooting down the planes. While inferior to their Japanese counterparts, there's still good ships: Saipan, Lexington, Essex, and Midway.
German Battleships: Extremely tanky, crazy secondary batteries, inaccurate main guns. They get sonar in the higher tiers to spot torpedoes with. These ships are characterized by their ability to tank damage and brawl like champs for brief periods of time - eating cruisers and destroyers alive with their secondaries, while piratically immune to torpedoes due to advanced (though temporary) warning from sonar. The difficultly of citadeling them makes them a tough opponent for enemy BBs at close ranges. Favorites are usually Gneisenau on up.
German Cruisers: Known for having bad high explosive but better than average AP. Also fairly tanky for cruisers because of their German turtlebacks. They have sonar that goes really far distances in the higher tiers. Hipper and Hindenburg probably most popular. Overall, a fairly 'meh' line.
German Destroyers: A very odd duck line of ships that changes quite a bit between every ship. You start with torpedo boats, then get stuck with a horrendous ship called the T-22. Then you switch to a line defined by slow-ish and large destroyers with sonar and ok guns with good AP for DDs but bad HE. Their own smoke lasts for a very short time. The sonar allows these ships to rush enemy smokes. Strangely, two of these ships have an option to mount larger guns than usual. Towards the end game, these ships strangely become hybrid gun-torpedo boats reminiscent of the Fletcher in the US line. I would NOT recommend these ships to a new player - even I don't really get them as is, though some players like them.
French Cruisers: Thinly armored cruisers that do well playing towards the back and lighting ships on fire. Kind of a mirror image to the German cruisers. They have the special bonus of speed boost that lets them move across the map easily with the T10 ship being able to hit an astounding 44 knots. Most destroyers can't hit 42 knots with speed boost on, haha. Best ships have panned out to be Algerie and Saint Louis.
British Cruisers: Good gunfire support ships with thin armor but powerful heals, along with smoke and sonar. They are good at going to a chokepoint on the map, smoking up, and firing lots of special British AP which is less likely to bounce off angled armor. There smoke allows them to cover themselves only as it only blows for a very short period. However, it lasts for a rather long time, allowing them to control an area. They're good at killing destroyers and ruining a battleships day if it gives its broadside. Fiji and Minotaur are most liked.
USSR Cruisers: Known for being squishy but also fast and good fire starters, gifted with rail gun guns (short shell flight time). They eventually get long range but short duration radar which makes them scary to destroyers. Kirov at T5, Budyonny at T6, Kutuzov Premium T8, and Mosvka T10 are the most popular.
USSR Destroyers: You need to pull out the Cheeki Breeki hardbass anthem on Youtube when you play these. They're fast, have bad maneuverability for destroyers, and terrible concealment. Their torpedoes suck nearly to the end of the line but their guns more than make up for it. They run around with their insane speed, dodge, light things on fire, and use AP on broadside cruisers at less than 7 km to absolutely ruin them with citadel hits. Their smokes aren't very good, and the last two ships can choose a heal in place of a smoke generator. Most famous are Kiev, Udaloi, and Khabarovsk.
USSR Destroyer Sub Line: These are more standard destroyers with torpedoes actually swimming some distance, and with some decent concealment. Their gun characteristics fall by the way side (in comparison to the main line) as they pick up the consumable Defensive Fire. While more typical as DDs, they're still large with poor rudder shift times, high-ish speed, and large turning circles. The smoke does not improve, either.
Edited by bacononaboat, 12 May 2017 - 06:42 PM.