I have over 1,200 games with a 74% win rate and have grinded every class.

Here is how I currently (7-3-2015) rank the ship classes and what could be done to even them out.

This assumes normal morale; if 200% morale bb's jump to #2

1 - CV (most dominant class in the game).

Decrease Aircraft space by 20%.  Planes should be precious at this point I don't even bother returning fighters home when they are low on fuel.

Decrease Acceleration by 20%

Decrease Turning rate by 15%

Bomber Loading Speed should be increased by 10%

Medium bombers can drop mines.

2.  CA

Decrease Acceleration by 15%

Decrease Turn Speed by 10%

Decrease Range by 10%

Decrease DP by 15%

Decrease speed by 5%

Increase base capture ability.

3. CL

Decrease Scout to 3

Ability to switch out torp racks for depth charges.

Remove friendly fire damage from mines.

4. BB

Decrease Scout to max of 4

2ndary guns should be allowed to attack surface targets like CA

Increase DP by 10%

Decrease acceleration and turning by 10%

Decrease overheat acceleration by 25%

5. DD

Decrease Depth Charge dmg by 35%

Increase Torpedo dmg by 15%

6. Sub

Increase speed of subs (non tier 11) to 27 knots and allow subs to overheat underwater.

Subs Sonar increases vision by 300% for 3 seconds after activation.

Reload time decreased by 20%

Torpedo dmg increased by 15%

Minimum arming range increased by 100%

Damage taken by shells at periscope depth (one) decreased by 50%

Reload status indicator for each torpedo tube