A funny observation of Trench Crusade lore
looking into the lore document, I noticed something interesting about how the Trench Crusade plotted out its battle history. When talking about land armies, fighting is relatively 50/50, with the current status quo being a stalemate (hence the trenches). On the other hand, we have the sea, where it appears that the Heretics have had massive success in bashing the fleets of the other powers, and seem to have gained naval superiority (not to mention inventing the submarine). This is to the point where it is mentioned that they were harrasing the English shoreline to the point of needing coastal defenses, and later on the fleet of England got wrecked hard by the Heretic fleet.
An interesting implication of this naval superiority is that since the Heretic Fleet captured Gibraltar in 1666, its likely that the Heretics have the ability to send people to the "New World".
In conclusion, it appears the forces of Hell rushed the naval tree to great success. On a secondary note, I think Heretic Marines would be a good force option to add in the game proper.