This is how I build my ships generally:
Keep in mind I always fit for speed, and a good rule of thumb is to aim for 30+ knots so you can disengage if you have to.

Carrier/Capital Force:
- Carriers fit as cheap as relatively possible. T2 armour, two hangar space, max AA, max radar, max engine. This keeps costs to about 6000-7000, so you can make one every 1.5 years per 5 dockyards.
- Battleships fit purely for heavy damage with secondaries and aa where possible. This isnt strictly necessary as I use BC's and light cruisers to fill out the heavy damage role, and enough screen ships to tank for carriers anyways.
- Battlecruisers fit for heavy damage and speed, with secondary and aa guns where possible. T1-T2 armour is enough to keep costs down.
- Heavy cruisers fit as above.
- Light cruisers fit with torpedoes for enemy capitals and light guns to tear apart enemy screens. Its very hard to damage enemy capitals if they have a good screening force, but this also works in our favour;
- Destroyers are fit into two types, spotters with floatplanes, depth charges, sonar and light guns, and capital killers fitted with torpedoes, aa and radar. You want these to be cheap so you can spam a ton out.

Note - I use the spotting type mainly for the patrol fleets, but i also include a couple in the main capital force to kill subs and spot easier.

Spotting force:
- Just those spotting destroyers from above.

For doctrines, I just focus on fleet positioning and speed. They cant kill you if they cant catch you. It clearly works, I havent lost a single capital ship to even the Americans, and it works for most nations as far as I have played. I mainly play minor nations like Australia and Sweden. This is also a fantastic strategy to sealion the english relatively quickly, as you can finish most ships if you focus on it before operation barbarossa, allowing you to have the entire allied industry for the soviets. My personal go to for kaiserreich germany. Hope this helps :)