The game you described sounds alot like a game called material girl from dieselmine. It was an alright game but it had alot of the components I tend to like in an RPG Maker game. I tend to like freedom of choice and a sandbox with a set objective but many options to hit that objective. As well as a character who starts as sort of a clean slate that you can sort of mold to your own tastes. Take advantage of what the RPGM engine does well and apply it to your game. Take advantage of the ability to create your own maps, and setup H stats or some way to track the growth of the character(s) as an example. If you are planning on making more of a Visual novel like game I would personally say don't use RPGM, use renpy; it is better suited for that.
I don't know what your plans are for your characters at all so it is hard to make suggestions but whatever your plans giving the player multiple routes to take and stories to unlock within your world will keep players coming back to the game. It gives you alot of opportunities to appeal to many different fetishes and demographics too with the open approach. If you want you could make a virgin / pure love route for vanilla audience, corruption or NTR for those who like it, Exhibitionism, BDSM, have fun with it and try and craft many different stories and outcomes for your characters. this can help your game stand out in my opinion.
Maybe I am talking out my ass since I am not a developer but from my perspective if a game allowed me lots of different options for what I can do and what lewd stuf I can get up to it will keep me interested.
