Nikki's return made the last week more interesting and it doesn't really matter to me because she was never going to win anyway + her impact on the series and the show as a whole makes it deserving she return.
If 'fake week' is referring to Charley's fake eviction I don't remember minding it that much since she was very enjoyable during it.
I didn't watch all of BB12.
Giving Conor half of the prize fund and essentially making him a runner-up finance wise is obviously TERRIBLE, but it's only one aspect to the twist. The plus side is that it led to the Deana vs Luke S feud in the last week that had me reeling from laughter 'CHARLIEEE? I WANT THE GOLD TICKET!'
The Safe house was iconic and led to Gina vs Hazel getting even more entertaining as a result
4in4out is far from perfect and I can see why people don't like it but for me the twins were quite overrated and I felt their feud with Jade concluded pretty well with them getting along at the end, Harriet started off okay but was a bit much sometimes and I didn't like her role in the Aaron/Joel incident, and I disliked Sarah and didn't really see much housemate value at all. Really Kieran was the only remote loss for me since I remember sort of liking him, but he wasn't an essential character to the series either. Harry and Sam are both positively received here so I'm surprised that this twist still gets negativity in spite of that and Simon's return led to the week following it to be quite enjoyable in his messy crying and self-destructiveness and the iconic ways he was repeatedly ended by Chole AND Eileen and everyone really. I dislike Marc in retrospect but his first two weeks following 4in4out I actually didn't mind him that much. I can see why people don't like this twist since it's very unexpected and not usual with how the show works but based on housemates that left/entered I don't hate it too much.
I'll go for the BB11 quad for making Josie arguably the most obvious winner ever and having no competition, for getting Corin unjustly evicted, and for making DAVE VAUGHAN the runner up
EDIT: **** I meant to vote BB15's pass to the final for Helen as well. Awful though as most know.