Setup looks familiar to lots of other games, but then I was positively surprised how unique the characters are and the story certainly will be.
Personally I liked the realistic look you go for a lot. Even the hairy armpits. Given the lots of pretty similar adult VN out there, I believe it certainly doesn't harm to look more into niches.
Besides as someone who is into femdom I see lots of potential in worshipping the mother as a natural Goddess. Only femdom game I know which really uses the scents of the women is "Tower of Trample". Would be nice to have the option to be into the females natural smells and tastes and have it used to humiliate the MC in some situations, e.g. rubbing mom's sweaty, stinky feet after a long day and well some harder stuff later on. Also smell and taste doesn't need to be rendered.
So should be relatively easy stuff to add, if that option is enabled...
Concerning choices, it's great how you seem to give people options to engage in stuff or not. Personally I am not much into Shemales, but if you combine it with other stuff I am into, like femdom, I can see myself, serving Alex too. If the Shemale stuff will be a forced path of dominating her, I will back away though.^^ So yeah, for now I kept it enabled, but will see where you go there. I mean you certainly will have to make some concessions to the amount of choices you will give the player, so the workload won't get out of hand. Dialogue so far seems to imply Alex will be a sub, so will have to see.
To summarize: Overall a good introduction and imho looks very promising for the future. Just keep mostly true to your vision of the game and I am sure your game will find its audience.