Wow, Cherry took every opportunity to criticize and insult the others. We get it- you don't want to be here- but making everyone else miserable doesn't help your situation at all.
Celeste seems like a nice girl who is an overachiever. But then when she finally blew up on Cherry, it turned out it was an act. She has a superiority complex expecting praise and is subtly condescending towards people who don't accomplish as much as her.
Liam is... flaky? He tries to play peacemaker between them, agrees with Celeste to earn her favor. I'm not sure why he's considered the "favorite"? His personality didn't stand out compared to the other two. Being a "careful planner" and all that was more informed traits as we didn't see him do them. There should have been a situation to see his logical thinking happen. An escape segment with different options and outcomes, and you either listening to Liam's advice (or is it actually Liam you're speaking to...?), ignoring him, or even abandoning your friends to save just yourself.
Giving the dog a chocolate was certainly evil (but other than Celeste scolding you it's just brushed over; should have had the dog get revenge in the Trick route), and lying about your costume was dishonest but not harmful, but choosing a decor to buy (with no way to refuse) and picking candy or a spooky plastic toy felt like arbitrary morality checks. Oddly enough, while 'Take only one candy' did show up, it didn't matter at that point with all the events before it. There was also no vandalism prank option (could have tied in with Liam creating a break-in plan to show his "careful planner") to deal with a rude neighbor.
I did enjoy how you could go the wicked route and naturally face karmic retribution with a more horrifying experience. Just wish the (Trick) options were more consistently cruel to warrant it. I also liked how offscript the Treat route devolved into by being a weird freak.
The doppelgangers/alternate realities glitchiness/time skips and loops/mindscrew of hearing different dialogue than your friends, were well done. I do feel there was a missed opportunity for a doppelganger (ideally Liam) to attack Celeste or Cherry and you're presented with a choice of who to save from dying. Would make your choices have meaningful consequences and also see how the survivor reacts. You could have also upped the confusion and chaos by having two different versions of your friends insisting you to follow them, presenting another weighted decision where you question who are the imposters.
The "Nobody would care if I died" scene felt stilted to me since Liam wasn't developed as much as the others (also the 'Middle Aged Woman???' speaker name just took me out since it removes the mysteriousness of them transforming into your friends). We didn't see a memory of what he was like in the past, what insecurities he had currently, or what his life is like now (again, the focus is more on Cherry and Celeste) that would make him desperately want to appease his childhood friends so that they wouldn't leave him. Basically, to have an emotional impact you need to build-up and provide reasons to care. Cherry's attitude made you dislike her instead, with 'no deep down she really cares', no it's bitterness and "I'm more mature/cooler" to the very end. The constantly warping scenarios, while creepy, also essentially reset any progress they could make in bridging their friendships. Though with the overarching theme of "These aren't your friends anymore" and the plot twist, I suppose this was intentional.
All in all, this was a great experience. My favorite design is Liam's pirate costume.