I am certainly a fan of:
- Card/deck games
- Quantifying mental states (excitement/shame points)
- Player narrative (the made up story running in players heads, derived by changing clothes/points)
- Anything that deals with clothing change (even if the visuals are only described)
- Gameplay focus (I have a short attention span and hate reading story, as a result my definition of 'exploration' is based on experimentation of game mechanics, not navigating a world)
I have no idea what ENF game is, nor have I played Slay the Spire, dominions, etc.
probably the biggest thing I am a fan of, is any situation where game mechanics try to represent some erotic setting. Be it designing 'trainer' games and representing the psychological state of the 'slave,' to currently right now I am making an AI that is able to perceive its surroundings, perceive others, perceive how the AI is being perceived (how they would be judged by other AI/player), be able to judge other AI, and ultimately react to unscripted events in dynamic ways, but still matching stylized personalities.
Ideas are cheep and plentiful, so I won't talk about it being good or not. Rather, what stands out to me is that you are starting with an idea that interest and excites you. I've had many such ideas, and I've started a lot of projects myself, but haven't released anything. I certainly like your idea, and would certainly like to talk about it more, the only issue I see however isn't the project, but the challenge of completing a project. Various things get in the way, from the realization that you need 30 pairs of clothes, and just getting one takes a week+ to get it drawn and into the game and coded; or maybe, while working and coding, you find a better style of mechanic you like, so you get distracted chasing after each new shiny cool idea; or worse you plan everything out and have a complete map of what it is you need to do, but then you think about the end of the game and wonder will players even find it satisfying, did the game do anything that makes you actually want to complete the game, or was just exploring these ideas enough for you?
I'm on and off working on projects, with art being my main challenge. Unless you hire an artist full time, its hard to have consistent art throughout the project's development and maturity, because artist have the same issues too, looking for the next new interesting project, not wanting to feel committed to any one project, etc. Assets online is one way to start, but there is never enough for a final product, only enough for a tech demo. after 7 years, I've only just managed to make my art palatable and consistent, and that's just female characters, not male characters or environment art.
So talking about the idea is fun, making a mock prototype with place holder art is a bit stressful because you are going through the phases of wanting to chase new cooler ideas and the cringe of having only placeholder art, but having a demo can really get people interested, inspired, and if an artist can see a framework, they can estimate how much work they need to put in, so it makes it easier to not just get an artist, but I find it also helps secure their interest for longer (because they have an idea of how much is being asked of them, and aren't intimidated by the idea of commitment if they can see an end).
Back to talking about your idea however, since that seems to be your focus for now and where your interest lies. I've toyed with similar mechanics, but probably for different lore/setting.
My main issue is I want to explain things, naturally work into things. So having a deck of cards in my case means, starting out with basic clothing cards, and having 'confidence' points to spend to upgrade your wardrobe or what you're willing to wear (meaning outfits have to have some statistic that quantifies how risky they are). While 'neat' that means the start of the game is slow, and that means making a batch of not that interesting set of assets (normal clothes). Then I start making the game more complicated then it needs to be, because I try to make the game mechanics tell a story. start the day, pick an outfit, pick an activity card, you do a thing, that card roles a dice for certain encounter types to happen with different probabilities, certain encounters will be narrated, and provide different 'points' and then some complicated system with all these different kinds of points that the player can then choose to spend in different ways to drive the story where they want it to go, allowing the player character to transform into different specific kinks (do they focus on their butt? get bigger boobs? become a bimbo? become a thick goth gf?), the idea is that the player, any player, can get what they want, but then now the workload is 100x because there needs to be a diverse set of clothes for each sub category, and the stages of transformation to each, and then the realization that most players won't see most of the work/art of the game, so its just too much work, argh!
That's basically how two weeks of talking will me will turn into, lots of cool ideas, but a project that is too big and intimidating to manage and make. One of the things I am practicing right now is ways of simplifying and minimizing. Rather than a character that the player controls, you write a character who is unique and has their own story, so there is only one storyline for the character to follow, so there is no issue of players controlling a 'goth' path or 'bimbo' path or anything, so that cuts out most of the work. that means you can focus on cloth designs that make sense for the character. If the character is pre writen, that means you don't need to worry about mechanics that simulate the mind (aka you don't need a ton of different point types), you can just focus on mechanics that match the character (excitement and shame).
so I invalidate anything I have to say, and move onto the next thing my mind sticks on, and that's the bigger picture. What is the goal, makes the game fun? Is it the game mechanics, the story? You say for now you "want to focus on compelling gameplay mechanics." That's great, but it also means nothing, that's like saying you want to make a car. What kind of car? You want to make a card and deck type erotic game, but what if I told you card type mechanics isn't a good enough answer? thats like saying you want to make a fast car, but you still haven't gotten into the details of the car you want to make. I don't mean, the mechanics you listed out, that's like listing out the parts you want to buy for the car, like car seats, battery, relay boxes. What I'm getting at is that you are missing something in the middle, and what you are missing is similar to 'terminology' or being able to describe the kind of car you want to make using 'car guy lingo.'
Here's what I mean. When you get into game design, and I mean really study game design, just as with any other discipline or profession, there are ways to measure things, ways to breakdown big ideas into smaller easier to define ideas. When you say you want to focus on "compelling gameplay mechanics" the issue is, there are different ways games are able to be compelling, just as there are different ways for cars to be fast. From what I've studied, games are broken down into 3 major categories for playing, Mechanics, Story, intrinsic alternative. every game has a mix of each, games where mechanics is #1 can have 3 types of mechanics (and again, each game can have a mix of each)
- skill type (are the turns timed? Do the players feel good about being able to perform?),
- puzzle types ( there is no timer, how much choice does the player have (how well do you code your random number generator or design your game mechanic such that you don't lock the player into unwinnable games?) there is only really one best answer per choice? Do the players feel good for finding a solution?),
- Investigative/exploratory (are players not locked into situations? are players free (able to back out? most easily measurable as 'is this a game where the player walks around')? are solutions separate from the obstacle (key to a door hidden somewhere else)? Do players feel good for discovery?)
Your game for example, sounds like you want to focus on game mechanics, and that you have a puzzle type game. even though you aren't thinking about your game like a puzzle, if its not testing a players skill (such as with being quick), and players can't escape a situation and possibly find a solution somewhere else, then it doesn't sound like the other focus types of game mechanics. If players are locked into a turn, that means they have to pick the best solution each turn, regardless if its for short term gain or a long term plan.
Then there is story, you don't have a story, but story, just like game mechanics, breaks up into multiple types of story. Your game has 'player driven narrative' where the story is in the players head. my own project, which focuses mostly on character interactions, and thus, writing, I actually have to treat the writing like a puzzle game, using the terms game designs use while designing puzzle games to know how to go about writing.
if this wall of text isn't proof enough, I could go on and on. since you are still developing your idea, and it sounds like it is more of a puzzle type game system, there are two things to investigate and explore. first is, how do players win (which it sounds like you are still exploring), and by knowing what steps are needed, how you can design the game so that it is winnable (how do the game mechanics interact or how does enemy AI play such that the game is winnable)? After that, is when you can explore other ideas, other game mechanic types, seeing how you can make it so its easier for players to win in different ways (basically allowing sub-optimal choices, balancing risk and reward) or ways for players to experiment and explore (but then you need things to explore, such as different character story types, ie goth gf. hence the project gets bigger).
with that said, the first question is, what is winning, how do you win this game? Is it becoming 'confident' enough to go out naked, or to be so excited getting caught that the character climaxes on the spot? Then there is the 'how.' you mention getting excited, but for me I've always wanted to use a 'confidence' point system to explain why things such as clothing cards become more lewd, or the idea of 'increased threshold' where the max shame points could increase, so that the narrative is that your character is able to be more confident because they are better able to endure more shame for the benefit of greater excitement, than I spend a bunch of time working out the reasoning for why the player character needs more excitement, what mechanic drives players to win?
anyways, I hope at least some of this was worth reading, I won't hesitate to go more in depth, ta ta!