Some hot tips for improvements:
1: No one likes to run around with out a plan, and just trying stuff over and over to get a different reaction.
Try and perhaps set a "!" on people that have some new dialog, or that will move the story forward. This goes for both the room pictures, and the characters them self.
Same with the search function.
2: If its going to be a pixel hunter game, the same thing applies there. Set a "!" above items that you can click, or you need to click to move the story. Cos otherwise its EXTREMELY annoying having to scan every environment for objects that might be clickable.
An alternative to this, if you dont want them to be super obvious, is a really helpfull hint system with a hint to where to find an item. Like for example: I should probably find out what Chloe have been texting about, she normally keeps her phone on her all the time tho. Maybe i can steal it when she is in the shower?
Or another one: I shouldnt search trough Chloes room when she is around, I need to find a time of the day when she is bussy,. Perhaps i can search her room when she is in the shower?
Or something like that!
3: Do not advance time, for interactions with people that dont do anything!
Trying to find out what to do, and every time you try to talk to someone, you get a none answer, and a movement of time. Is really annoying. This in combination with point 4, is really a nightmare for sandbox games tbh.
4: Enable rollback! Easy as that, without it, especially sandbox games are just super annoying.
5: The 2 talk/search buttons are up in the corner, it would be better if after clicking a character, at least the talk button ended up in the middle of the screen. This is a minor one, but it makes navigating the game a lot easier.
Using a lot of screen real estate on the sides for buttons is good for visuals, but it can be really annoying to navigate.
There is a reason why many games try and bring your dialog buttons, to the center of the screen.
6: A walkthrough, or a really good in game hint system. (This ties in to point 2. Cos it needs to be easy, if you dont want to go down the "!" route)
The important part of a good hint system in game tho, is that it needs to be easy and quick to navigate. No more than 3 preferably 2 clicks to see the hints.
A lot of games fail at this and have great hint systems, but you need to do 5-7 clicks on your phone to get to them.
Like for example: Mobile phone - Hint app - Girls - Quests - Chloe. And then you need to hit back in the bottom corner to click on the next girl. This is no bueno!
Best is to have a separate icon for hints, (thats on the main screen) and then just pictures of all the girls as icons on a screen, and you click one to get a hint.
7: You write, that there is going to be a lot of incest. Just dont forget about Patreon TOS. You need to have a patch or some system for the game, so its not incest enabled for patreon downloads. Or you WILL have issues, sooner or later!
The cardinal sin of sandbox games, is grind, and trying to stretch content. By making stuff hard to play, or having people guessing where to go, what to do and such.
I honestly only played your game for 10min, not cos dialogs where bad, not cos story or renders where bad.
It was 100% the way the sandbox was built!
I cant comment on the game it self really, but these things needs to be better, for people to actually want to find out.
Not trying to be mean, cos i understand you put a lot of effort down, and its a first release. But these things are HUGELY important for the success of a sandbox game.
Good luck!