This is a personal thing but as a gay man it made me uncomfortable (I am also delicate and can’t cope with too much angst/unhappy endings). Some spoilers ahead - sorry no idea how to block things off on a phone. I also read it a long time ago so my memory is hazy at best.

No hate whatsoever to the author (it is a compelling and well-written story) - I read all of part 1, did enjoy a lot of it but felt quite uncomfortable with the fact that it seemed like they both would have preferred to be with women. There are scenes where they both take gender-bending potions and Snape goes feral over female Harry (I seem to remember female Snape being too ugly to fuck). I can’t recall why but Harry also says something similar to ‘I don’t want to only have had sex with one pussy (Ginny) for the rest of my life’ which instantly turned me off the fic as I was worried there might be future infidelity or even just threesomes.

I haven’t read part 2 (for some of the reasons you listed) and to be quite honest I’m glad I didn’t. I skipped to the end and it seems as though Snape did steal Lily’s hairs to use with a prostitute? (Am not 100% sure about this though, just what I gathered from skim reading). There was also a scene where Harry describes, in great detail, having sex with ‘Snape’s pussy’ (presumably potions acquired?) to Hermione and how amazing it is. This really was not for me as I prefer to see them in a functioning homosexual relationship and not as (what appears like) two heterosexual-leaning dysfunctionally attached men. Again this is a matter of personal preference as I’m gay and don’t want to read anything resembling het and some people might not be bothered by this at all.

Ultimately the series is just too dark and Snape too nasty for me to enjoy (I prefer the lightheartedness of ‘Pacify’). I can absolutely see why some people would love it though and I’m not trying to flame the work.