I thought that grimness will hook the player so he remember game longer. But I like wife too, and I think we need to try to get it back, or not remove it at all, as you suggest. One of my ideas is make her alive again as an undead, lol.
I think grim is good. It makes the situation more believable. Also the dead wife is a good opener for whats to come.
Alot of H games are just porn, i think it will be best to go for a game with actual world building.
grim or dark fantasy is not always the way but the game already plays with the theme of famine and food scarcety.