Alright, so here we go, my final suspects: Nimsy and Arx. (With slight suss on JaDe.)
After spending, like, an hour looking over the entire thread, here's why I think so:
gio7sm as Steven Universe
Bidoof FTW as Magic: The Gathering : Gio's power was mentioned in the first post and the two have been inseparable in the narrative, and
this post specifically shows gio compiling notes for Doof out of several other posts - why would the hater go to such trouble? Then again, it might benefit one of them to decieve the other, but their powers have been time tested and even JD confirmed that Doof was not suss.
apocalypseArisen as Homestuck : more assassination attempts than you can shake a stick at.
Ninja Aiden as Code Geass : Rezzed, therefore not the hater.
Kiyoshi the Polar Bear as Fallout : I'm not the hater, and the clues don't point towards me whatsoever. To boot, I was mentioned in the roleblock D6. (I believe that was D6)
jdthebud as Hunter x Hunter : Clues can only be linked through creative stretches of thought, and his behavior towards his suspects seem pretty legit.
JaDe.X105 as Attack on Titan : Has never used his vigilante power, and has been mentioned in a post about how Tales caught sight of him "doing nothing." My least suss suspect.
Arx as Dragon Ball Z : Has literally never posted anything remotely useful, and does not have a power, but rather,
a restriction. Has proven throughout his seldom posts that this is a legitimate rule for him,
but how does that make any sense to Dragon Ball Z? Also has been mentioned in several posts about how he "grumbles." Seems odd for an inactive player to do. Also, I'm pretty sure he's missed some votes and not been chastised for it. Clues also lead to him a bit, too. My most suss.
Link to his posts:
https://www.pokecommunity.com/search.php?searchid=6778354
Nimsy as Legend of Zelda : Claims to have had a one-time kill power (weird, having a duplicate of JaDe's) but she was noted to be in the D6 list of nullified players and has had a story that follows through with that. Though, only one person died that night
on inactivity. She hopped on early to the Netto bandwagon, though. The clues also fancy her. She hasn't been super active, albeit having nearly double the amount of posts that Arx has, but strange she's popping in her head so close to the end ... where one deicision might seal her win if she is the Hater.
Link to her posts:
https://www.pokecommunity.com/search.php?searchid=6778358
Don't jump on any votes,
these are a start, not a condemnation. Input your own thoughts and observations.