If Gaijin add subs in the future I would like to see some for the french tech tree :
Classe O’byrne
Classe Français
Classe 600-630 tonnes
Classe Sirène
Classe Ondine
Classe Circé
Classe Requin
Classe Saphire
Classe 1500 tonnes
Classe Aurore
Classe Minerve
And the mighty Surcouf
And thats only a small list theres still some out there without counting the captured ones
They can easily compete against U boats