Hey, thanks so much for the message! I will say that you pose very interesting questions.
Protagonist transformations
I have plans for the player to change dick size, nothing else so far. I did get asked to make gender change content, will think about it!
As for customization, probably not since it would be difficult to create with this kind of content. Throughout the story there will definitely be opportunities to change yourself.
Cumflation
I actually have not thought about this, but I do very much like the idea. In terms of how much, I'm just going on a limb on how I would make this, but I would probably make this depend on dick size, if that makes sense.
Cruelty
Right now cruelty will only make the subjects automatically sedated at the end of the intro. But yes, if there ever would be rape in the game, this would be included.
More fetishes
As the game progresses, for sure. I will say some fetishes will be more prioritized at first, as this is simply the nature of a game with this many fetishes.
Characters
As the game is open world, my goal is to create quite a lot of characters. And of course, this is a lot of work, but that is the plan and we will see how it goes. As for how different they'll be, I would say I want most characters to have their own story line. Some side characters could also be used to host more diverse/niche fetish paths.
How many chapters
So, as the game is just at its beginning, I can't really answer this question. My intention is to periodically keep releasing updates, see where that brings me.
Bestiality
I have not thought about this, but I will say I am not a fan of this, unfortunately. I'm not opposed to adding suggested fetishes, but this one, really unsure.
Control
The idea of the game is to have a lot of branching content, so yes, some choices will matter. Right now this is already the case, although you can't actually see the consequences yet.
NTR
Alright, so, it was suggested to me to add the NTR toggle, because people are either very into this, or completely turned off by it. As for antagonist/rival, I have personally not thought about it this way. More like, certain events that involve random characters. For your question if they can grow, I'd say yes, but this completely depends on the context of the scene.
Futa/trans
For this, I can't promise anything, but maybe. I feel like the game needs to be fleshed out more first.
Either way, I'm very glad you enjoyed!