Incredibly valid point. It is a far more complex question than for or against.
For now, I have a scenario for trans and alcoholism planned. As for the abusive one and any other potentially more controversial topics I cannot comment on how they would be implemented just yet but I can rule out explicit depiction of SA and anything surrounding that topic for a start.
In terms of the trans element:
A friend of mine thought they were trans (male to female), and they were planning on having top surgery but as time went on and their own self-image as well as their perspective on themselves both mentally and physically changed she eventually decided that she would not have top or indeed bottom surgery. She continues to take hormones, prefers she/her pronouns, and generally prefers to dress more effeminately (I understand to some that is a superficial element, ultimately it’s how you feel inside but that’s part of how she expresses herself in this space and as such is a massive part of her mental health in relation to her transition) she may never fully transition. She may eventually detransition but that is not up to me or anyone else to speculate because whilst I may not fully understand this in its entirety I do understand what these choices represent for her mental health and as such I support her. In terms of this game I would like to explore this process but from a female to male perspective. The underlying essence of this storyline would be that as they gain weight (as this is a weight gain game) and as they try to force their body into the image they feel it should be (chest binders, Spanx, etc) they eventually come to terms with the fact that while mentally they may not feel like the woman they were biologically born, they actually like how they look on this more feminine spectrum (fertility type femininity) and it ultimately leads to them accepting their duality of a biological female whilst in the core of their being feeling they should and could be male.
This may seem like a gross oversimplification but I feel this could work well if handled correctly. I may or may not be the person to pull this off but I do think it would be a good way of shedding light on this side of the topic without making it feel forced, coerced, tokenized, or any some such “tacked on” character development never to be referenced again.
In terms of the alcoholism:
As a college student myself I understand that not all alcoholism is smashing beer bottles and passing out in your own vomit. While this is another gross oversimplification it is also how many people perceive it. A reliance on alcohol can range from an intrinsic need to go out and party, a habitual practice of having a few beers when you get home that then becomes more than a few or not knowing your limit and constantly drinking more and more to reach that drunken numbness to deal with stress or anxiety. My future father-in-law falls into the last category, my best friend the 1st, and myself to some extent the 2nd.
In terms of this game, I would likely utilize the 1st example as it fits with the college theme but may explore it to a lesser extent with the player character in the 2nd example as this would play into a fetishized role of intoxication but to a much lesser extent as I, again, do not intent to romanticize these topics. With the “party animal by night” becoming “party animal at all times” identity I would like to explore the effects of constantly going out partying with one specific NPC that unbeknownst to the player character is developing a dependency and broach how the player character in this instance would deal with this. Unlike the trans scenario, this one would be far less passive and require player interaction to ultimately observe the effects your actions have on the characters around you.
As far as other touchy subjects, as I’ve said SA is out, I almost certainly will not be touching narcotics, no underage, no necro, no bestiality, and quite a few more things in that vein but until the inspiration strikes I don’t know which topics would ultimately end up as “touchy subjects”
Hopefully, this clarifies where I’m coming from and where I intend to go with it.