Just create a thread here in General Discussions, give us what you already have in mind and design and use the thread to gather suggestions and ideas, f95 is massive and centered around lewd games, I doubt there is an easier way to gather ideas and feedback.
Lewd game are hard to build when it comes to making them not as a boring scene builders, that's why people like MGI so much, because it mixes lewd and easy gameplay in a good way (for the genre), interesting story and stylish designs help too. Even though it is still a VN in essence, just much more interactive.
Simple and fun.