It's very kind of you to go out of your way to address our feedback here, but you don't need to go far to find out what the best course of action is. After all, listening to just opinions here may at best give you 1/10 of the entire image. Right now only specific group of people has become attracted to your game whom share 3 characteristics at this point:
*They don't like that you can't reuse old saves
*They don't like the fact that there is not much hardcore content
*They became upset at the puzzle
What does it tell you? That all of the people who became attracted to your product and downloaded it here did it to...to put it bluntly...rub one quickly out. However bad it sounds, most of the people don't consider this game anything great(maybe even at the level of forgetting it couple days later)...which is normal! It's not a big game for now at least.
So what does this objectively mean? Your game is A) Nice to the eye B) User-friendly - it doesn't repel most casual audience here C) It gives good first impression
But there is nothing more than that. To learn implications further you need to look at other big games that currently have wider audience like SummertimeSaga, Milfy City, Four Elements Trainer etc etc. Let's take first for example - people there don't complain at the fact that they can't reuse old saves(on a bigger scale)...Why? Because they like the game to the point where they don't mind wasting away extra hours. But why do they like the game? Is it because SS exceptionally good? No! Most of these people simply got used to it while the game was still very novel and standing out in the market(There are other games that are simply better yet due to bad decisions early on didn't manage to stand out enough) The Dev then came up with the myriad of reasons why they can't make old saves work resulting in people having to replay game everytime(which in result made them feel that every update was super big despite them being actually not that big, what a devil!)
So what does this first point tell us? If you don't want to constantly worry about health of your project your game must either leave big enough impression early for people to not mind replaying it or the *replayability* of the game must be increased. Unfortunately increasing replayability of the renpy game is rather stupid task, so the best shot will always be trying to leave lasting impression on your potential audience so that they don't forget about your game right away.
Porn is very simple field, craft storyline, make it spicy, put some suspense here and there and make people interested. The most common mistake devs do here that I also noticed is trying to flesh out the game first before releasing hardcore content - terrible mistake unless you don't wanna earn more cash and stay where you are. One must understand that people use porn to jack off and jacking off to handjob or other mild content won't be satisfactory enough for most people.
Focus on one storyline - making it awesome enough for people to anticipate another similar update - repeat. Also, if you get one storyline to a decent point from scratch and then start another one you won't have to worry about introducing save compatibility anytime soon. Brilliant, is it not?
Next, don't think about hard methods to make every update play longer. Minigames are nice addition - but only if everything else that is actually relevant is in check. What most devs do is introducing something like money so that player needs to think about something else other the thing in his hand, which is logical and easy - it doesn't make people who come here to rub one out quickly annoyed at least, and leave it at that.
Substance, substance, substance! If you see a guy writing "omg waited 2 months for 30 minutes worth of content". Ignore the fucker, he is a trap. The dude will leave, you will never see him again but instead he will pull you to think that you should do whatever it takes to increase the length of next update. Then it will lead to artificially making it longer - MISTAKE! Of course, releasing 5 minute long update isn't good either, no pain no gain!
Instead of trying to be overly ambitious, it will definitely pay out better to focus on key areas until you can afford attention to other things and when the audience grows big enough to appreciate it.
So...make it short, make it hot for a simple B0b to understand but don't make it cheap(Quality of art and dialogues comes there).
Since I've written this much already I may also add another observation of mine - (free of charge too!) - manipulate the version number wisely, people will get more attracted to version numbers like 0.8 1.0 etc(some cheeky bastards took advantage off it and got burned too!). Be aware that once you release around 7-8 updates there will be a rise of people interested to try out your game especially given that art looks very good and it will be *extremely* crucial to hook as many of those people as possible. If you can manipulate version cleverly until you will feel ready that game is ready to take it head on then great.
As a closing note, more of a personal remark - when it comes to sex scenes specifically, their arrangement, details etc, my best advise for you is to check out trends on fakku and what most popular artists do here. There are some common points in every work that you can easily take advantage of to more easily appeal to potential patrons.
From the top of my head: Vanilla vanilla vanilla...you will crash once you step into ntr. Vanilla is king right now friend, I am not saying this because I like it myself, quite the opposite in fact, it's insipid, but it's true that 70% of the perverts out here prefer vanilla content.
Corruption - making your characters progress in any way will make people more invested. From there you can branch out to various fetishes, incest etc. If you don't want for your game to feel cheap, you need to plan this very carefully! In this regard, you probly should take example of games like TaffyTales or some of Icstor's games. Key words moral conflict, degeneration, various taboos, going from one extreme to another.
Of course you don't need to worry about MC having to follow on every storyline and coding hundreds of scenarios, just be clever with dialogues. Seperate storylines cleverly.
...just remember that purpose of this kind of game isn't to blueball people(I am looking at you Mr. Dots). Also writing is equally important as art in the game. Some dudes out there manage to produce humongous results with text based porn games alone...I am sure you can understand what this means.
Hope I was able to relay the message.