Leaving aside the excellent work that the balance and control represented with this version.
Half gathering several topics, I would like to ask the following:
I know that working with this game isn´t as fast or easy as it may appear to be, but ... it is possible that you can take advantage of the things that already exist:
1. The night monster, the meme / rumor until it is confirmed, can have its own difficult transformation that depending on how the PC develops in its encounters with the creature and what advanced traits it has, that transformation may turn out to be harmful or beneficial for the PC (example: that said transformation allows the PC to move faster, hide or even be able to do unique things, but in exchange for said transformation the PC needs something to live or not to go mad )?
It is that the transformations leaving aside time and requirements, are too easy to obtain or don´t represent a greater weight or change in the PC, so that one was difficult or was a double-edged blade would be interesting to see.
2. If point 1 is very difficult or you don´t like, continue with the night monster, since the forest where the hawk / harpy is doesn´t have many events or areas, that place or rather, below it (for the areas in that forest that leads to underground places) be or give rise to a labyrinth and that in said labyrinth is the home of the monster, which protects something and if the PC obtains that something, then the PC acquires the ability to use said labyrinth in order to move between areas faster or spy on others, but with the danger or condition that the monster always tries to recover that something or catch the PC?
3. And the simplest. Since the mechanism of pregnancy is difficult (mechanical or ethical) to calm a little the craving that we all (myself included) have for said mechanics in particular, what if taking advantage of the fact that there are so many Slime-type creatures, tentacles or aquatic fantasy type, why not add the transformation of Slime or a variation / proximity, Scylla?
A beneficial factor of the one of Slime or Scylla, is that said transformations (depending on the version that is inspected in the case of Slime) is that both transformations the "pregnancy" requires or would require more time and once the PC gave birth in Instead of an egg, what would come out would be rather a creature that in its early stages was a pet type, but that after time and effort could help or harm (depending on what is done) the PC.
In this way, leaving aside the fetish of pregnancy, one and more if you are playing in a game without cheating, if you want to acquire this transformation (which should present some advantage so that in a normal game one wants it for something else there of the fetish, such as: that it gave improvements to learning or to the development of the body) after obtaining it, one from that point plays with more head to prevent that if one is not prepared for the longer time that "pregnancy" requires or Taking care of the creature until it is ready to be independent and even help, this results in problems or immovable marks for the rest of the game that hinder progress, kind of Civilization when you make a bad decision and the game becomes extremely difficult (more than it can already be by one's choices).
Anyway, I already make my point.
Again, excellent work with the version, the wait was worth it and I hope this project can come to an end, whatever the goal or point is.