Honestly, in my opinion, what the game is lacking now(not counting the bug fixes on the way), is probably variation of animations. As people were mentioning here, relating to NTR legend and others - it could be better. Additionally - the clothes. There are variations of clothes for the female characters in the game, distinctive for each of them, yet in H-scenes they are always fully naked. Kinda makes it nearly all the same.
Also i mentioned some idea for development to the dev, but he's busy with dlc in mind right now. My point was - if it's already NTR oriented game even with it in the name. There is basically half of that genre lacking here(where either male or female MC is NTRed by others) so potentially half of the people that are looking into the genre would skip this game, and the general idea was - to add another boss-character to the game for example, something like part-timer trainer that comes to the dojo few times per week, player fights it just like Rika, and if he lost - the guy would 'train' the girls instead of MC, while MC can only watch the events in dojo or act in the city for a day. Basically all the mechanics that are already in the game. And maybe even with corruption progression in that, it would add some more challenge and long-term interest to the game, as well as interest another half of ntr-genre fans in the game.