Interesting game. I always love the aspect of having to earn the H-scenes in these types of games so I understand and am all for designing the game with this level of challenge. With that said, some fine tuning of the difficulty such as not allowing certain enemy types to spawn before a certain point, allowing mobs to lose aggro somehow, reducing the range the gunners can attack, etc. can go a long way to ease players into the flow of the game.
Will definitely be following the development of this game.