1. Have Eva develop and control her anger and not hurt anyone. Take counseling of some sort, since she clearly regretted her behavior in The Big Sleep. It'd be funny if it were Bridgette, since Eva hated Bridgette (which otherwise went nowhere) and she was able to help others find their center through yoga and whatnot.
2. Have Gwen interact with Lindsay more, and heck maybe Beth by extension. They could have bonded over hating Heather too.
3. More Gweoff broship.
4. Blame Duncan for the love triangle too (coming from people who aren't Courtney or Cody).
5. Teach Cody to be less of a preppy entitled white kid.
6. Have Sierra use her Total Drama knowledge to become a legit threat and not just revolve around Cody or Cameron.
7. Have Ezekiel try to imitate more styles rather than the hip hop look from Celebrity Manhunt and Total Drama World Tour. Make it a running gag maybe.