I'm open to adding new things if I like your idea and I can implement it without breaking anything else in the process.
here is the French translation.
New Game Plus keeps most of the Original Story intact and adds some new sex opportunities. You can now have repeatable sex with each woman in a single playthrough, essentially creating a harem.
General Changes:
No more hissing sounds in Ashley's room
Ashley's room can now also be locked and unlocked using Mysterious Key
Girls don't get mad if you grope them
Some girls like it when you cum on them
Peeing on girls may annoy them, but won't affect your relationship status
Girls who see you having sex will start masturbating
Most of the time, people will not comment when you take your dick out
Leah will ignore alcohol being given to people
Quest to get rid of Frank given on game start
Pick-up lines that piss women off are gone
When 2 girls are engaged in cunnilingus, you can interact with the girl with her ass up and join in with some doggy style.
Simon Says returns with extra content! Available after finding and reading Madison's diary.
Some sex positions are unavailable during Wall Sex 3, to prevent you getting stuck inside walls when changing positions. If you like to switch positions a lot, save Wall Sex 3 for the final position to give yourself more freedom of what you can change between.
Specific Changes:
Amy:
Condom added to inventory shortly after Amy asks for it
Made Truth or Dare in the hot tub with Amy and Brittney a lot sexier. You can even take the photo Amy needs and then invite her back for more.
Can invite Amy to Ashley's room for sex after completing Scavenger Hunt.
Conversation with Amy after she leaves the hot tub always convinces her to strip down to only her panties.
Ashley:
Quest to have a threesome with Ashley and Madison, under the guise of reconciliation. Given at game start
Repeatable Wall Sex option with Ashley opens up after she gives you a BJ as a reward for cleaning her clothes
Brittney:
Truth or Dare in the hot tub includes sex options with Brittney
Frank:
Can demand weed from him without paying
Once you have the weed, get Katherine the rum and give it to her, then tell Frank to release the booze
Once he has released the booze, tell him he has outlived his usefulness and follow him to the garage
Tell him once more to leave and enjoy the show before watching him disappear for good
Katherine:
When Katherine asks you to flash everyone at the party, you can just flash her then tell her you flashed everyone
Leah:
Once Frank is gone, you can ask Leah to have sex in any location
Leah always swallows after a BJ
Madison:
Threesome with Ashley when you give them each 3 natty lites and invite them upstairs
*New* After reading Madison's diary all the way through, you will have access to her phone code and the nude photos, allowing you to confront her about it and blackmail her into sexual favors
Starting The Muse quest ends Simon Says
If you start the plan with Ashley and Vickie to secretly video Madison, Simon Says will become unavailable
*New* Madison will suck your dick after painting your portrait before Derek interrupts you
Whichever way you complete The Muse, you can have sex with Madison afterwards.
Rachael:
*New* Can ask Rachael to invite Vickie Vixen once you have learned of her existence
Can ask Rachael to make out once she is interested enough in you
No matter what dares you choose for Rachael to do, she will fuck you at the end
Repeatable sex options added, available after first time sex with Rachael
Stephanie:
*New* Steph can be convinced to go topless after giving her whip-its and complimenting her dance moves
Once topless, Steph can be asked for sex lessons
*New* Steph can be invited into the hot tub once she is outside dancing near it
*New* Steph can now take part in Sexy Truth or Dare with Amy and Brittney
*New* Steph's Drunk and Disorderly no longer ends with her breaking her teeth
Vickie:
Vickie is always down to fuck
*For those experiencing glitches such as players no longer being interactable or falling through the floor when loading a save, SLOW DOWN. I have had these problems before. These glitches can occur even without my mod installed and are generally caused by clicking through dialogue too quickly. Wait for people to at least say a few words before skipping over them, and save often. A corrupted save will never load properly again. If you have a save from before triggering the glitch, it should work to replay from there, but at a slower pace to avoid it happening again.
I hope this helps

For those who would still like to enjoy the original voice acting, follow these steps:
Find the New Game Plus mod files. For me it was automatically put here: Documents\Eek\House Party\Mods\Stories\New Game Plus
Select all files in this folder and copy them.
Find the Original Story location. As a Steam user, it was located here:
C:\Program Files (x86)\Steam\steamapps\common\House Party\HouseParty_Data\StreamingAssets\Mods\Stories\Original Story
Once here, delete existing files.
Now paste the files you've copied from New Game Plus mod into the Original Story folder.
With all files selected, right click and go to properties, then check the box to make the files Read-Only. This way they will not be overwritten when the game launches.
Rename New Game Plus.story so it is called Original Story.story.
Now when you launch the game you can play New Game Plus with voice acting restored, by choosing Original Story from the main menu. (there will be an error message, ignore it)
When you want to play the real Original Story again, simply delete all the files in the Original Story folder and re-launch the game. All original files will be automatically downloaded.