In WWII there were not only aircraft carriers, battleships, cruisers, destroyers, transport ships and submarines, they also had subclasses and each of these subclasses had its specific function, to add the following you would first have to add the following:

-mines of water: (stealth), these would cause damage to enemy ships and allies that pass through their location, they would only have a single use so they can only do a single damage. Mining ships could place mines at up to three points before returning to a port to resupply, submarines could only place at 1 point before returning to a port to resupply, and highly successful ships could place mines at 2 points, but these they would take 50% more. They could be resupplied at a naval base and a local port of their own or allied, they can also be resupplied from a resupply ship.

-ability for small boats and boats to navigate the rivers. Make a river system on the maps.

-structure: bridges, these would be built on the rivers.

-structure: river base, it would have the capacity to produce gunboats, cutters, corvettes and mini-submarines.

-Divide the ocean into deep water and shallow water.

LARGE VESSELS:

1. AIRCRAFT CARRIER:

.Fleet Aircraft carrier: This carrier is the same as the one in CoW right now. However, it would have more antiaircraft capacity and could repair planes by up to 15%.

.light aircraft carrier: this aircraft carrier is faster and smaller than a fleet carrier and has less aircraft capacity but can go in a fleet. It would be destined to accompany the fleet aircraft carriers in the attack. It can repair airplanes by up to 10%.

.Escort aircraft carrier, this is a type of aircraft carrier much slower than a fleet carrier, it is smaller than the light but has similar aircraft capacity, it can detect submarines of the same or lower level, this aircraft carrier cannot embark tactical bombers due to its size. It would be destined for the defense of the fleet and hunting submarines.


2 BATTLE SHIP

.Nothing, the battleships only had one class, battleships and their only function was to attack other ships and positions on land, 100% irreplaceable.


3.CRUISE.

. Combat cruise, this would have the purpose of accompanying the battle ships as a complement to attack and defense. If it is escorting a fleet it would have the ability to receive 75% damage if it is attacked by ships.

.Heavy cruiser, this would be slow, tough and would have the current antiaircraft capability of a normal CoW cruiser, but would not have great vision range.

.Light cruiser, it would be decently resistant, fast, when escorting a convoy and it is attacked, it takes 75% of the damage if it is attacked by airplanes.


4. DESTROYER

.destroyer, steria the same as now in CoW. But this one would have a range and attack range.

.Escort Destroyer, when escorting a fleet, she would have the ability to take 75% of the damage if she is attacked by submarines.

. frigate, this would have moderate antisubmarine capacity but would not have attack range.

.miner, this would have the function of laying mines and tracking enemy mines, it could place mines at up to three points before needing resupply.

.Dragamines, this would be in charge of tracking and destroying mines, ideal to ensure the passage of convoys.


5. SUBMARINES

.submarines, would have the same characteristics of the current CoW submarine.


6. NODRISA SHIPS, deployment and resupply of units.

. Seaplane mother ship, it would have a great vision capacity, it could detect submarines of the same level or lower thanks to its seaplanes, it could embark, refuel and repair only 1 naval bomber unit by up to 15%.

. resupply ship, this ship can carry resources in it, 1 single ship can resupply up to 3 ships and repair them by up to 20%, after supplying all possible ships it needs resupply, it needs a naval base, local port or a resupply ship to resupply ._. .It cannot be used for the attack due to its limited armament.

. mother ship of submarines, these ships could resupply submarines and mini-submarines, it can repair submarines up to 30%, this unit can detect submarines, however it cannot be used for the attack due to its scarce armament.


7. TRANSPORTATION BOATS

.transport ship, this would not change.

.Trade switches, these would be intended to fight transport ships, these ships are transport ships modified to fight other transport ships and smaller vessels. They would have a medium attack range but with little resistance.

. Blockbuster ships, these ships would be destined to break, spur and attack cutter ships that carry out blockades of rivers, canals, etc. They would have a major attack on shallow water vessels and would not be affected by a naval blockade. You can also lay mines but it takes 50% longer to do so.

.Hospital ship, this ship when joining a damaged convoy can heal it 1 time in up to 30% of hit points, it can attend up to 1 time before needing resupply, it can be resupplied at a naval base, a local port or a ship of resupply.


SMALL SHIPS, ability to navigate rivers

1.minisubmarines, it would have less anti-ship capacity and less speed but it could go by rivers. Although she too she can go in the ocean.

2.cutter, this would have a great range of vision. She would be destined to observe enemy positions near rivers and coasts in shallow waters, she could also make blockades to rivers, and beaches.

3. Corvette, this would have antisubmarine capacity but could go by rivers. She can only go through shallow waters


4.ponton, this would be a shallow water unit transport, this would be faster when embarking units, but it can only go through shallow water.

5. gunboat, this would be like a battle ship but with shallow waters like rivers and beaches. she could destroy bridges, river bases and naval bases, she would have a small attack range.

6. torpedo boats, these would have no range of attack but would do moderate damage to ships and submarines can go through shallow and deep water.

7. Torpedo hunters, would serve as torpedo hunters and if they are escorting a convoy and it is attacked by a torpedo hunter it would receive 75% of the damage.

THANK YOU FOR READING, HAVE A GOOD DAY AND DON'T FORGET TO USE A MASK AND KEEP 1.5 METERS AWAY FROM OTHER PEOPLE. DON'T FORGET THAT WE CONTINUE IN PANDEMIC AND RESPECT THE BIOSECURITY RULES. BYE BYE.

I know, it's highly anticipated to add a long-range recon unit, but you can't deny it, this idea here got you excited:
. Seaplane mother ship, it would have a great vision capacity, it could detect submarines of the same or lower level thanks to its seaplanes, it could embark only 1 naval bomber unit.
This unit can be like an aircraft carrier only because of the reconnaissance seaplanes they propose. It meets all the requirements: 1 existed in real life 2 has purpose 3 can create strategy, I would be very happy if you add this unit along with reconnaissance seaplanes. I SEAPLANE