People were introduced into the circle a replacements last year too. It does put them at an advantage, but they can also band together.
The biggest change so far has been the Joker. I thought that was an interesting spin, but not too detrimental.
The mannequin challenge was a tricky way to out catfishes. The best part is that Emily had no clue until it was being presented that he would get roasted for it.
The fixation on catfishes is interesting. It really doesn't matter if someone is a catfish, so people shouldn't be so preoccupied by it. They should be focused on making friendships. Though I suppose that identifying someone as a catfish calls their authenticity into question which puts them at risk.