Nico has been at the top of my 'axe list' for a while now. I mean no disrespect but the actress just doesn't have the acting chops necessary for such a complicated character. Like usual, they've over egged the pudding by turning her into a serial killer with no remorse when with a better actress (and no intentional killings) she would have had potential.
Cameron's not far behind either. Completely 2D. The Lomax girls haven't worked as a unit since Sam and Danny's deaths either. The only thing I'm remotely looking forward to is seeing the dynamic between them and Amy. The worst current family by a mile.
Ste is so repetitive that it's draining to watch, and I can't wait for Amy and Barnsey to rip into him. I would say Harry too but he's not as bad away from Ste, although if he's going to persist on sticking by him they can ride off into the sunset together, never to be spoken of again!
Diego and Scott are spare parts, and I don't think many would miss them if they were to leave.
I'll give the Donovan's more time to settle in before making a judgment. Again, Marnie needs to be toned down and be given more development rather than constant meddling and manipulation. I cannot stand Lisa but again, I wouldn't axe her yet.
I would have said Freddie a few months ago, but I don't think he's been as bad lately now Lindsey's out the picture. The Roscoes are much better now they're trimmed down. Holly and Maxine, IMO, can still be redeemed. Both (in particular Nikki) are competent actors. They just need to get Maxine away from anything involving Patrick and allow her to move on, and stop making Holly jump from man to man.
So,
Nico
Cameron
Leela
Tegan
Peri
Ste
Diego
Scott