I know i am late to this but i personally don't care about pretty much anything as long as it's optional, i am not a big fan of NTR in general but there are games out there that do it right, either as comedic non-canon stuff or just introduces a villain for the MC to overcome or combining both. Honestly in recent times i really like the villain approach, lots of games on the site are fairly boring, vanilla, straightforward where the biggest choice in the game is whether or not you wanna receive a blowjob or a footjob. This is why i found myself playing more unique games lately rather than the same old "You live with your landlady and her other tenants" and that's the whole premise.
I found your game to be very unique and fun, it doesn't fit the typical mold of other games so i say keep doing whatever you think is best.
Although as some have said just the mere mention of NTR even if it's completely optional and non-canon is enough to reduce them into a whimper mess, unfortunately too many people are fragile nowadays, but it is what it is. Still from the business perspective the NTR tag can also turn a lot of people away, probably turn a lot more away then towards your game, so if you are gonna put it in the best choice is to have it in a patch as you mentioned therefore the game doesn't receive an NTR tag and no one can stumble upon it by sheer accident, they have to actively seek it out to get it.
Anyway love the game so far, keep up the great work.