Hi, can you both elaborate on this. What would you like to see to make it more deep? (examples if possible).
Increase the love between the two, when the relationship is not deep, it is like seeing sex between two strangers, but the deeper the relationship, the more the feeling of NTR, you can do this by increasing the romance dialogues and events between husband and wife
in sharing and cheating and similar, use teasing elements a lot. It can be done by comparing the size of the dick or the performance in bed or the amount of handsomeness, etc.
Make the issues bigger, I don't mean to the extent of manga and manhwa that traumatize the reader, but to an average level, for example, when betrayal happens, both the husband will be upset (he won't forgive her soon) and the wife will regret it (she will feel guilty for a while)
--------------------
The things I wrote above are some of the basis of the concept of NTR, they all exist in this great game to some extent, but when more attention is paid to them, this game will certainly be much better.