@LCloud
If you want suggestions then here are a few:
-Try to make your game less generic, to give you an example a game made with the same engine (I think it's the same rpg maker type) that seems a lot more worked on is the RPGM game called "farmer's dreams" by MuseX. Just when I started your game the only feeling I had is "generic RPG maker game".
-Second is that you have to truly plan ahead, personally I think it could have been more interesting if rather than fusing with the mother she just died. If you want to make the MC a futanari there are better ways, like for example your demon race has both masculine and feminine reproduction systems until they decide what gender do they want to be.
-Third is try to list what fetishes are you gonna add, in an adult game what people see first are fetishes and it's quite important that while you are starting you list them all. It will determine what type of support you are gonna get and while seeing what fetishes your game has people only find "Transformation - Futa Protagonist - Lesbian", well the MC while it's interesting to say that it's a futa it isn't a fetish, lesbian makes people ask something like "do you consider a futa a girl and because of that it's lesbian?"
The first thing that I truly recommend you is, take a white paper and list what fetishes and pairings do you like for the game. Being a futanari there are people that like futanari on male, others prefer male on futanari and others like futanari x female. There are many fetishes that can be added or sexual acts, just think of what you like first, for example you like anal sex? then anal fetish for your game, you have a foot fetish? then so be it and obviously monster girls, demons... it doesn't matter that you don't list them all HOWEVER you have to be very clear about the so called "heavy fetishes", one example is NTR, it's important to say from the start if it's gonna exist or not in your game, those should never be added during development.
After you have the fetishes you need to think about the game structure, this is the most important part because it defines your game, do a half assed effort here and the game will be nothing. The most important thing is to think about custom stats and things that will make your game different then work to enable it on your game, what is your focus? relationship evolutions? do you like treasure hunting and random events?, how about churches, perhaps a church of corruption?, there are many ways to choose from here and if you have played some games you will know them.
Finally you go to the characters and their interactions, talks, character changes...
P.D: It's absolutely recommended to not give annoying quests from the start, killing rats as first quest is annoying.