My AMC Guide
(kind of turned into a book lol)
of course you want to win every war, and the biggest win you can get is by forcing the opposition to collapse by revolution
in order to get the opposition to collapse, you need to starve the population and gradually drive up the unrest level until they overthrow the government and sue for peace
there are 2 main ways to accomplish this - either blockade the home area, or launch a massive raider campaign and sink enough enemy merchants to raise unrest. yes there is a 3rd way where you can get the random option of sending a revolutionary there and 'hope' they overthrow the government, but that only really works if you'v already driven up unrest, and otherwise it can backfire and drive up your own unrest
in order pull off a blockade you either need a larger navy than the enemy, or you need to take the time to whittle down the enemy's navy to the point where you can start a blockade
problem is that you need at least 1 base in that sea zone, otherwise you will lose a LOT of ships to internment, which means likely only the British and USA can pull off a blockade with no home base in the area and still keep enough ships to maintain it after losing many ships to internment
blockade is the easiest way to cause a collapse since it's less 'work'
otherwise, the other option is to build raiders to cause a collapse. it is more micro, but if you can't blockade and you want (the best chance) to win the war then you gotta do what you gotta do
the big complaint is that it costs a lot to build AMCs, then all the ships get scrapped after the war so it's a big waste of money, but that's a short-term way of looking at it
building raiders is an investment - if you get the enemy to collapse, then you get points to spend either on acquiring new colonies (generally not recommended unless it helps you or hinders the enemy in the long run), or you can invest these points back into your economy (which is the best long term action)
i know the game allows you to create warship raiders and it's tempting to go that route, but in the past i'v tried every variation of using warship raiders and it's just not practical - it costs a LOT for the numbers you need, you likely don't need raiders every war so it might be a waste, and losing a raider cruiser to internment or being sunk hurts a lot more than losing a nameless cheap AMC
of course to build AMCs you need budget set aside - it costs about $5000(k) per turn for 4 turns per set of 12 (of my design) to build, so when tensions are ramping up you should look at possible opponents, decide if you might need AMCs if you get in a war, and if so either hold off on building new expensive capital ships until after the war starts and you'v built your AMCs, or save a huge pile of cash so you can build needed AMCs without going into debt
how many to raiders to build? - raiding does not work with just a few ships, you need numbers - i play on Very Large Fleets and i personally go with 72 (six groups of 12 ships), but you can go with less for smaller fleet sizes (i think i did 48 on Large Fleet size). the reason being is once i build my raider fleet at the beginning of a war i don't want to build any more for the duration, and usually by the end of the war i'l be down to 20+ AMCs remaining. the other reason for building all the raiders i need at the start is that once i finish building all the raiders i'l need i can then use the freed up budget to build my next set of capital ships which should be completed either by the end of the current war or shortly after. once that batch of capital ships is launched i might concentrate on smaller ships until the next war so my budget isn't tied up on long construction projects (or you could halt construction on costlier building projects to build AMCs, that's less efficient but wars don't happen on a 'schedule')
how often will you need to use AMCs in a war? - depends on the country you are playing:
Japan and USA have no colonies in other home seazones so they are both most likely to need AMCs - of course USA can generally "brute force" a blockade wherever they want since they can build a massive fleet and can afford to lose ships to internment, but it's also easier to set aside budget to build AMCs which allows you to free up your fleet for colony protection/invasions/etc
Italy/Austria-Hungry/Chin China/CSA each have access to one other nation's home seazone so will likely need to use AMCs, but not necessarily in every war
the rest of the nations generally will have access to most other home areas so the decision to build AMCs will lie with whether you are able to blockade the enemy or be able to whittle down their fleet to be able to blockade
how to use AMCs - unless your AMCs are actively blockading the enemy (rare), AMCs MUST move every turn, because the very first turn that AMCs enter a seazone is their most effective turn, after that the ai sends ships in and usually your AMCs are countered. create 1-2 death stacks of AMCs, have 1 move in and out of the enemy home area, and the other can roam around the enemy's colonies which hopefully splits up the ai's ships up
always auto-resolve raider battles - you taking control of the battle will not reduce the chance of it getting caught and sunk, it was already caught so accept that it will likely get sunk. accept only fun battles - running away in an AMC is not 'a fun battle'
the best AMC design - you want disposable and cheap, don't waste your time making it survivable since if it's caught it's likely sunk no matter how fast or well armed you make it
don't make AMCs long range, but give them reliable engines - long range is very expensive (less so with diesel, but stick to cheap), it's only benefits are they are slightly more effective at raiding and have a slightly better chance at evading, but it's not worth the cost. reliable engines are cheap, and greatly reduce the chance of AMCs getting engine problems which reduces the chance of getting interned
give them mines - AMCs roam everywhere so might as well sow some mines as well
give them 1 floatplane - it makes AMCs better at their job. don't bother with hangers or catapults - since you are auto-resolving battles you don't need to protect or deploy the aircraft, and again keep it CHEAP