Wargaming made the promise while still in beta that they would NEVER add subs to WoWS. Another broken promise. As for the reported in game speeds for subs of 25 to 30 knots is just silly fantasy. No WW II submarine traveled on the surface or submerged at more than 22 knots. American fleet subs were fast on the surface with a rated speed of 20.75 kn. German type XXI had a top submerged speed of just under 18 kn. A thirty knot sub did not exist until nuclear powered. Wargaming needs to drop this idea as it cannot be balanced in the tactical game setting that is WoWS.
Wargaming made several bad decisions from the beginning with CVs. 1. CVs were added to the game. Should not have been included in the first place. 2. CVs have always been over powered and by their nature will always be OP. The massive amount of mistakes in CV loadouts, damage, and spotting just becomes a tl,dr post.